During April at Ferny Grove overnight temperature were below average. Daytime temperatures were close to average and the coolest in 11 years. In the Brisbane area most of the official sites observed below average overnight temperatures and were over 1 ºC below average at some inland sites. Daytime temperatures as observed by the official sites were below average at most locations. Rainfall at Ferny Grove was above average and the highest in 6 years with most rainfall occurring in the first week of the month. In the Brisbane area the official sites observed near or above average rainfall totals. At Ferny Grove air pressure was below average, mean relative humidity was near average, mean minimum relative humidity was below average, mean maximum relative humidity was above average, mean minimum and mean dew point was below average, mean maximum dew point was near average, wind speed was above average and there were 0 thunderstorms (1 thunder day).
Temperature – below average overnight and near average daytime temperatures
Monthly Mean Daily Minimum Temperature: 14.7 ºC, 1.4 ºC below average and 1.3 ºC lower than same month in 2020. This is the second lowest on record for April and the lowest since the current record low of 14.6 ºC in 2017. The mean minimum temperatures observed by the official sites in the Brisbane areas were below average at most sites and over 1 ºC below average at some inland sites. Logan City Treatment Plant was however close to average being 0.5 ºC below average with a mean minimum temperature of 15.6 ºC. Most of the sites observed mean minimum temperatures that were between 0.6 ºC below average at Cape Moreton Lighthouse (18.6 ºC) and 1 ºC below average at Brisbane (16.4 ºC) and Redcliffe (15.6 ºC). Some inland sites saw mean minimum temperatures that were more than 1 ºC below average being 1.9 ºC below average at Amberley (12.1 ºC) and 1.7 ºC below average at Beaudesert (12.4 ºC). The highest mean minimum temperature was observed by Cape Moreton Lighthouse and the lowest mean minimum temperature was 11.2 ºC at Canungra.
Monthly Mean Daily Maximum Temperature: 26.5 ºC, equal to the long term average and 2.6 ºC lower than same month in 2020. This is the third lowest on record for April and the lowest since 26.1 ºC in 2012. Mean maximum temperatures observed by the official sites in the Brisbane were generally cooler than average and near average at some sites. The sites measuring close to average mean maximum temperatures were Archerfield and Cape Moreton Lighthouse at 0.3 ºC below average with a mean maximum temperature of 26.3 ºC and 24 ºC respectively. Beerburrum saw the greatest negative anomaly from the long term average of 1 ºC below average with a mean maximum temperature of 25.6 ºC. The remaining sites saw mean maximum temperatures that were between 0.6 ºC below average at Redcliffe (25.4 ºC) and 0.9 ºC below average at Brisbane (26.3 ºC), Brisbane Aero (25.2 ºC) and Gatton (26.3 ºC). The highest mean maximum temperature of all the official sites was 26.5 ºC at Amberley (0.7 ºC below average and the lowest mean maximum temperature was 24 ºC at Cape Moreton Lighthouse (0.3 ºC below average).
Mean Monthly Temperature: 20.6 ºC, 0.7 ºC below average, 2 ºC lower than the same month in 2020. This is the equal lowest on record for April equalling the current record low of 20.6 ºC in 2017.
Lowest Temperature: 9.1 ºC on 23 April 2021 at 6:19 AM. Same month in 2020 was 11.9 ºC. This is the lowest on record daily and monthly minimum temperature for April on record exceeding the previous record of 9.8 ºC in 2015 on 27 April at 6:10 AM. Official stations in the Brisbane area observed the lowest temperature of the month at most sites on the 23rd and at some sites on the 22nd and 24th. The lowest was 3.8 ºC at Canungra on the 23rd and the highest was 15.5 ºC at Cape Moreton Lighthouse on the 23rd. In the Brisbane area most nights were cool from the 12th to the end of the month. Brisbane observed its lowest temperature of 11.6 ºC on the 23rd.
Highest Temperature: 33.7 ºC on 10 April 2021 at 1:24 PM. The same month in 2020 was 34.2 ºC. This is the second highest monthly and daily maximum temperature for April on record and the highest since the current record high of 34.2 ºC in 2020 on 17 April at 3:19 PM. The official sites measured the highest temperature for the month at all sites on the 10th. The lowest was 28.6 ºC at Cape Moreton Lighthouse and the highest was 33.1 ºC at Amberley and Greenbank. The highest temperature observed at Brisbane was 33 ºC on the 10th. During the month there were warm days on the 9th to 11th and at some sites on the 15th and 16th and 21st. Brisbane Aero observed the highest maximum temperature for April on record of 32.3 ºC exceeding the old record of 32.2 ºC in 2006.
Lowest Daily Maximum Temperature: 21.7 ºC on 4 April 2021 at 1:23 PM. This is the fifth highest and lowest daily maximum temperature for April on record on monthly basis, the equal seventh lowest daily maximum temperature for April and the lowest since 18.9 ºC in 2015 on 30 April at 12:00 AM. Same month in 2020 was 24.7 ºC. The official sites measured the coolest day of the month on the 22nd at many sites and on the 4th and 30th at some sites. These ranged between 21.1 ºC at Cape Moreton Lighthouse on the 22nd and 23 ºC at Point Lookout on the 22nd. Brisbane observed 22 ºC on the 22nd. Throughout the month there were several periods of near or below average temperatures.
Highest Daily Minimum Temperature: 20.4 ºC on 6 April 2021 at 2:24 AM. This is the fifth highest daily highest minimum temperature on record for April, the lowest since 19 ºC in 2019 on 20 April at 5:11 AM, the eight highest daily minimum temperature for April and the highest since 20.6 ºC on 4 April 2020 at 6:39 AM. Same month in 2020 was 20.6 ºC. In the Brisbane area the warmest nights occurred on the 6th at many sites and on the 3rd, 11th and 17th at some sites. These ranged between 19.9 ºC at Canungra on the 6th and 22.2 ºC at Cape Moreton Lighthouse on the 11th. Brisbane observed 20.9 ºC on the 6th. Most warm nights occurred in the first 11 days of the month associated with rainfall and cloud cover with very few warm nights during the remainder of the month.
Monthly Mean Minimum Grass Temperature: 13 ºC (1.6 ºC lower than same month in 2020).
Lowest Daily Minimum Grass Temperature: 7.7 ºC on 23 April 2021 (2.9 ºC lower than same month in 2020). This coincided with the lowest minimum air temperature of 9.1 ºC for the month.
Highest Daily Minimum Daily Grass Temperature: 19.9 ºC on 6 April 2021 (0.9 ºC higher than same month in 2020). This coincided with the highest minimum air temperature of 20.4 ºC for the month.
Highest Minimum Grass Temperature Depression: 3.1 ºC on 12 April 2021 with a minimum grass temperature of 8 ºC and an air temperature of 11.1 ºC.
Lowest Minimum Grass Temperature Depression: 0.3 ºC on 3 April 2021 with a minimum grass temperature of 19 ºC and an air temperature of 19.3 ºC.
April minimum temperatures were near or above average in the first 10 days of the month before an extended period of below average temperatures during most of the remaining of the month. The 1st and 2nd were 1 ºC above average, 3 ºC above average on the 3rd and 4th, 4 ºC above average on the 5th and 6th, 3 ºC above average on the 7th and 2 ºC above average on the 8th. On the 9th it was close to average, 1 ºC below average on the 10th and 1 ºC above average on the 11th. Cooler temperature followed being 5 ºC below average on the 12th, 3 ºC below average on the 13th, 5 ºC below average on the 14th, 3 ºC below average on the 15th and 2 ºC below average on the 16th. The 17th was 3 ºC above average before a 12 day period of below average with the 18th being 3 ºC below average, 4 ºC below average on the 19th and 20th, 3 ºC below average on the 21st and 6 ºC below average on the 22nd. The 23rd was 7 ºC below average, 6 ºC below average on the 24th, 5 ºC below average on the 25th, 3 ºC below average on the 26th and 2 ºC below average on the 27th. On the 28th it was 3 ºC below average, 2 ºC below average on the 29th and was 1 ºC above average on the 30th.
Maximum temperatures during April were near average or below average throughout the month with some above average temperatures. The 1st and 2nd were close to average before a cooler period of 3 ºC below average, 5 ºC below average on the 4th, 4 ºC below average on the 5th and 3 ºC below average on the 6th. Warmer days followed with the 7th being 1 ºC above average, the 8th was 3 ºC above average, the 9th was 5 ºC above average, the 10th was 7 ºC above average, and the 11th was 3 ºC above average. The 12th and 13th were 1 ºC below average and was close to average on the 14th. The 15th was 3 ºC above average, 4 ºC above average on the 16th before cooling to 2 ºC below average on the 17th, 1 ºC below average on the 18th and was near average on the 19th. The 20th was 1 ºC above average, warmed to 4 ºC above average on the 21st before cooling to 4 ºC below average on the 22nd and then was 2 ºC below average on the 23rd and 1 ºC below average on the 24th. The 25th to 27th was close to average, 1 ºC below average on the 28th and 29th and 2 ºC below average on the 30th.
The mean year to date temperature of 23.7 ºC was 0.3 ºC below average and the lowest for January to April since 23.5 ºC in 2013.
Heatwave Conditions (Maximum temperatures): Nil
MSL pressure – below average air pressure
Monthly Mean Daily Minimum MSL Pressure: 1014.6 hPa (0.4 hPa higher than same month in 2020). This is the fourth lowest for April and the highest since 1018.9 hPa in 2019.
Monthly Mean Daily Maximum MSL Pressure: 1018.7 hPa (0.3 hPa lower than same month in 2020). This is the third lowest on record for April and the equal lowest since 1018.7 hPa in 2018.
Monthly Mean MSL Pressure: 1016.7 hPa (0.8 hPa below average, 0.1 hPa higher than same month in 2020). This is the third lowest on record for April and the highest since 1020.9 hPa in 2019.
Lowest MSL Pressure: 1004.6 hPa on 10 April 2021 at 3:21 PM. The same month in 2020 saw 1006.4 hPa. This is the second lowest monthly minimum air pressure for April, the third lowest daily April minimum air pressure and the lowest since the current record low of 1002 hPa in 2011 on 14 April at 2:58 PM.
Highest MSL Pressure: 1024.8 hPa on 14 April 2020 at 8:47 AM. The same month in 2020 saw 1024.8 hPa. This is the sixth highest April monthly maximum air pressure on record, the highest since 1026 hPa in 2019 on 4 April at 9:27 AM, the equal sixteenth highest daily April maximum air pressure and the highest since 1025.6 hPa on 5 April 2019 at 9:49 AM.
Note: Air pressure measurements are being closely monitored to maintain its accuracy. Over the month of April, a difference of 0.4 hPa lower compared to the official BoM Brisbane site – No. 040913 was observed which is deemed as not meeting the expected accuracy.
Relative Humidity – near average mean humidity, below average mean minimum humidity, and above average mean maximum humidity
Monthly Mean Daily Minimum Humidity: 51.8 % (8.6 % higher than same month in 2020 and 3.1 % below average). This is the fourth lowest on record for April and the highest since 54.4 % in 2019.
Monthly Mean Daily Maximum Humidity: 95.3 % (0.4 % higher than same month in 2020 and 3.3 % above average). This is the second highest on record for April and the highest since the current record high of 95.6% in 2018.
Monthly Mean Humidity: 73.6 % (4.6 % higher than same month in 2020 and 0.1 % above average). This is the fifth lowest on record for April and the highest since 73.9 % in 2019.
Lowest Humidity: 27 % on 21 April 2021 at 3:33 PM (2 % lower than this month in 2020). This is the second lowest monthly minimum humidity for April on record, the lowest since the current record low of 18 % in 2020 on 5 April at 3:02 PM, the fourth lowest daily minimum humidity for April and the lowest since 26% on 20 April 2020 at 12:42 PM.
Highest Humidity: 99 % on 6 April 2021 at 4:33 AM (1% higher than same month in 2020). This is the equal highest monthly April maximum humidity on record equalling 99% on 5 April 2015 at 6:15 AM.
Dew point – below average mean, below average mean minimum and above average mean maximum dew point
Monthly mean daily minimum dew point: 12.3 ºC (1.8 ºC below average). This is the second lowest monthly mean minimum dew point for April on record and the lowest since 12.1 ºC in 2017.
Monthly mean daily maximum dew point: 18 ºC (0.6 ºC above average). This is the third lowest mean maximum dew point for April and the lowest since the 17.3 ºC in 2017.
Monthly mean dew point: 15.2 ºC (1.2 ºC below average). This is the second lowest monthly mean dew point for April and the lowest since the current record low of 14.7 ºC in 2017.
Lowest dew point: 4.2 ºC on 12 April 2021 at 3:15 AM. This is the third lowest monthly minimum dew point for April on record, the highest since 8.6 ºC in 2019 on 5 April at 2:19 PM, the fifth lowest daily dew point for April and the lowest since 2.9 ºC on 12 April 2020 at 2:15 PM.
Highest dew point: 22.6 ºC on 4 April 2021 at 3:30 PM. This is the equal fifth highest monthly maximum dew point on record for April, the equal sixth highest daily dew point for April and equalling 22.6 ºC in 2020 on 4 April at 5:24 PM.
Wind Speed – above average wind speed
Maximum Wind Gust: 35 km/hr on 11 April 2021 at 8:00 PM. This is the fourth lowest maximum wind gust on record for April, the lowest since 19.4 km/hr in 2013 on 3 April at 3:17 PM, the equal twenty-sixth highest daily wind gust for April, and the highest since 37 km/hr in 2020 on 30 April at 8:54 PM.
Maximum Wind Speed: 18 km/hr on 11 April 2021 at 3:01 PM (Light Force Wind). This is the third lowest monthly maximum wind speed for April on record, the lowest since 15 km/hr in 2019 on 19 April at 1:02 PM, the thirty-fifth highest daily wind speed for April and the equal highest since 21 km/hr on 2020 on 30 April at 9:07 PM.
Wind Run: 2004.1 km (1031.8 km lower than same month in 2020), 91.9 km below average and 1 % below average. This is the third highest on record for April total wind run and the lowest since 1220.8 km in 2018.
Monthly Mean Wind Speed: 1.8 km/hr (1 km/hr lower than this month in 2020), 0.9 km/hr below the long term average). This is the fifth lowest on record for April and the lowest since 1.7 km/hr in 2018.
Daily Mean Maximum Wind Gust: 23 km/hr (0.7 km/hr higher than this month in 2020), 2.9 km/hr above average and 30.5 % above average. This is the sixth lowest daily mean maximum wind gust on record for April and the highest since 24.6 km/hr in 2019.
Daily Mean Maximum Wind Speed: 10.7 km/hr, 0.6 km/hr lower than this month in 2020), 2.9 km/hr above average and 74.5 % above average. This is the second lowest on record for April and lowest since the current record low of 8.9 km/hr in 2012.
Dominant Direction: SE (SE this month last year).
Rainfall – above average rainfall
Monthly Rainfall Total: 130.1 mm (36.3 mm above average) and 138.6% of the long-term average. This total is in decile 9/ 82nd percentile which ranks as high and 52.2 mm above the long-term median (308.1 % of long term median). This total is higher than this month in 2020 which was 13.5 mm, the seventh highest on record for April and the highest since 133.2 mm in 2015.
Long period rainfall totals improved for most periods as compared with April 2021. Many of the long period totals remained slightly above average or above average, though the longer time periods of 24 and 36 month have remained with negative anomalies. 6 monthly rainfall dropped slightly by 13.4 mm to 71.8 mm above average (decile 8) and 9 monthly rainfall improved slightly by 20.2 mm to 86.2 mm above average (decile 7). 12 monthly rainfall improved by 113.9 mm to 7.3 mm above average (decile 4). 18 month rainfall improved by 69.5 mm and was 93 mm above average (decile 7). 24 month and 36 month remained below average which improved by 109.9 mm to 14 mm below average for 24 month rainfall (decile 5) and improved by 60.1 mm to 165 mm below average for 36 month rainfall (decile 4). 48 month rainfall improved by 135.2 mm to 24.9 mm above average (decile 5). Compared with the same period in 2020 the long period rainfall totals improved and significantly for some periods but have worsened for 36 and 48 monthly totals. The greatest improvement was 18-month rainfall from 209.1 mm below average to 14 mm above average and greatest deterioration was 36 month rainfall from 175.4 mm above average to 24.9 mm above average.
In the Brisbane area the official sites observed near or above average rainfall totals. Many sites observed totals that ranked historically as high that ranged between 128 % of the long term average at Gatton (61.2 mm) and 183 % of the long term average at Brisbane (112.2 mm). The remaining sites observed totals that ranked as average ranging between 89% of the long term average at Cape Moreton Lighthouse (127 mm) and 127% of the long term average at Beaudesert (53.8 mm). Brisbane observed a total of 112.2 mm which ranked as high and was 183 % of the long term average. The highest total of all the official sites was 235.1 mm at Peachester and the highest total of the main official sites was 143.3 mm at Cape Moreton Lighthouse.
In the Brisbane area most rainfall fell during the first week of the month. On the 16th and 17th a surface trough produce showers in the Brisbane area.
Number of Rain Days (0.1 mm or greater): 9 days, equal to same month in 2020 and equal to the long-term average. This is eighth highest on record for April and is the equal highest since 16 days in 2019.
Highest Daily Total: 53.8 mm on 6 April 2021. This is the sixth highest daily total on record for April on monthly basis, the thirteenth highest daily total on record for April on daily basis and the highest since 55.2 mm on 29 April 2012. The highest daily total in the Brisbane area of all official sites was 143 mm at Peachester on the 6th.
The year to date total rainfall was 649.4 mm (124.6 above average and 20 % above average) and compared with previous annual totals for the same period is the lowest since 352.8 mm in 2019 and the eleventh highest on record. This is lower than the January to April rainfall total in 2020, which saw well above average rainfall in January and February in contrast to near average rainfall in 2021 until the above average rainfall in March and April 2021.
The year to date number of rain days of 59 was 15 days above the long term average. This is the highest on record as compared with previous January to April totals since 65 days in 2018 and the seventh highest on record.
Monthly Rainfall Total – (automatic gauge) 24 hours to 9am: 109.4 mm (20.7 mm less than the site official standard gauge and within 15.9 %). Highest daily total of automatic gauge, (24 hours to 9am): 43.8 mm on 6 April 2021, (24 hours from midnight): 41.6 mm on 6 April 2021.
Note: This automatic gauge for the month of April, did not reached the expected accuracy (of +/- 10% of the standard gauge) at -15.9%.
A moderate to heavy shower in the mid afternoon with some light showers, then some moderate falls later in the afternoon before light showers in the evening on the 1st. On the 2nd was light showers in the first half of the early hours with 11.5 mm was measured on the 2nd. Some very brief light showers in the evening of the 2nd were followed by brief light showers in the early hours and in the early morning and light showers in the morning on the 3rd. 0.4mm was measured on the 3rd. Light showers until the mid afternoon of the 3rd with a light to moderate shower in the mid afternoon and in the early evening. On the 4th were light showers tending to light rain periods from later in the early hours with 8.6 mm measured on the 4th. Light rain periods eased in the evening before intermittent drizzle and light rain from early on the 5th before light rain from the morning with 8.7 mm measured on the 5th.
Light rain increased to light to moderate falls later in the evening and early on the 6th before light falls. Drizzle and light rain from the morning of the 6th with 53.8 mm measured on the 6th with some light to moderate falls in the evening. On the 7th 31.4 mm was measured as drizzle and light rain at times cleared in the morning. In the late morning were light showers with a shower in the mid afternoon with brief moderate falls with 2.6 mm was measured on the 8th. In the early to mid-afternoon of the 8th were brief light showers with 0.3 mm measured on the 9th. A light shower in the late afternoon of the 17th, then a moderate to heavy shower in the early evening that was followed by some light showers during the rest of the evening. 12.2 mm was measured on the 18th. A light shower in the late morning of the 30th, light to moderate thundery showers in the early afternoon before some light brief showers in the mid-afternoon and early evening, with 7.9 mm measured the following day.
Most of the rainfall during the month fell in the first week where the monthly rainfall total on the 7th had reached 114.4 mm. Based on consecutive daily rainfall totals, the first 8 days of the month was the wettest period for April since 406.8 mm in 1990.
There was 4 days with falls of at least 25 mm (6 less than same month in 2020) with 10 days of less than 1 mm (4 less than same month in 2020).
Highest rainfall rate was 103.8 mm/hr on the 17 April 2021 at 6:37 PM. This is the second highest monthly and daily rainfall rate for April on record and the highest since the current record high of 188.8 mm/hr in 2019 on 20 April at 4:41 PM.
The highest hourly rainfall total was 13 mm on the 6 April 2021 at 12:01 AM. This is the fourth highest hourly rain for April on daily and monthly basis and the highest since 14.2 mm in 2019 on 20 April at 5:20 PM.
Number of severe thunderstorms: 0
Number of thunderstorms: 0 (Mild: 0, Moderate: 0)
Number of thunder days: 1 day
Number of nearby storms: 0
Severe thunderstorms of note in the Brisbane area: Nil
Remarks for month
- Cloudy with the temperature variable and generally stable from the late morning to the mid-afternoon and briefly became cold in the late afternoon on the 1st. Very high relative humidity in the afternoon as the relative humidity rose.
- Cloudy at times on the 2nd.
- Mostly cloudy on the 3rd. The temperature was stable from early and the temperature was variable from the mid-morning to the mid-afternoon while generally falling. Low relative humidity in the early hours and rose and fell several times in the morning and afternoon and became high or very high from the late morning to the mid afternoon.
- On the 4th the temperature was stable or rose slowly early in the day and the temperature cooled during the morning and to cold in the afternoon as the temperature rose slowly and became stable in the late morning and in the afternoon. The relative humidity became high and stable in the morning and afternoon.
- Cloudy on the 5th and the temperature rose slowly from the morning to the mid-afternoon. In the morning and afternoon, the relative humidity was high or very high.
- It was cloudy on the 6th with it hot early in the day as the temperature fell slowly during most of the early hours. The temperature became cool in the afternoon as the temperature rose slowly in the morning and early afternoon. The relative humidity was elevated and stable over the entire day that was high to very high from the mid-morning to the late afternoon.
- On the 7th the rainfall eased with cloudy skies easing to cloudy at times. The temperature fell slowly or was stable during the early hours with the temperature quite variable in the late morning and in the afternoon. High relative humidity from the mid-morning and in the afternoon with the relative humidity rather variable.
- Sunny in the morning and mostly sunny in the afternoon of the 9th.
- Sunny on the 10th with the temperature rising quickly in the morning and was hot from the mid-morning and in the afternoon. The relative humidity fell quickly in the morning and became low later in the morning and in the afternoon.
- On the 11th it was sunny in the afternoon. The minimum temperature was reached in the mid early hours before rising later in the early hours. The dew point fell in the late afternoon and evening and became low in the evening. Relative humidity became very low in the evening after the relative humidity stabilised from the late afternoon.
- Sunny or mostly sunny on the 12th with low dew point in the morning. Relative humidity was very low early in the day and low in the morning.
- Sunny with the temperature variable from the mid-morning to the mid-afternoon on the 13th and 14th
- Mostly sunny on the 15th.
- Sunny on the 16th.
- Mostly cloudy on the 17th with some showers later in the day.
- Mostly sunny on the 18th with the temperature variable in the afternoon.
- Sunny or mostly sunny on the 19th and 20th
- On the 21st it was sunny. In the afternoon the dew point fell and became low from the late afternoon before easing in the evening. As the relative humidity fell in the morning and afternoon, the relative humidity became low or very low in the afternoon and evening before easing in the evening.
- Cloudy on the 22nd. A cold morning and became cold in the mid to late afternoon. Low or very low relative humidity in the evening.
- Sunny on the 23rd with a cold morning. Dew point was low in the morning before rising later in the morning. Relative humidity was low early in the day and in the morning that fell quickly during the morning.
- Mostly sunny with a cold morning on the 24th.
- Mostly sunny on the 25th.
- Mostly sunny in the morning of the 26th and the temperature was variable from the late morning to the late afternoon.
- The temperature was variable from the late morning to the mid-afternoon of the 27th.
- On the 28th and 29th the temperature was variable in the morning and afternoon.
- On the 30th it was cloudy at times, with the temperature falling later in the morning before rising in the afternoon and became cold in the mid to late afternoon. High to very high relative humidity late in the morning and in the afternoon.
- 14 day of dew: Light - 8th, 9th, 14th to 22nd, 27th to 29th.
Weather influences
- A high pressure system near south-eastern Australia extended a firm ridge across most of the state that extended moist onshore flow along the east Queensland coast on the 1st and 2nd.
- On the 3rd the high pressure system shifted into the Tasman Sea while extending a ridge over much of the state that started to decay. Moist onshore flow remained in place.
- A high pressure system shifting east over the Tasman Sea on the 4th extended a decaying ridge over the state, while a surface trough over the western Coral Sea sat broadly parallel to the east Queensland coast. An embedded sub-tropical low pressure system offshore of the central Queensland coast shifted southwards. An upper level low pressure system extended over the central inland. The combination lead to unsettled conditions over eastern Queensland.
- On the 5th a high pressure system in the Great Australian Bight shifted eastwards as a high pressure system in the Tasman Sea shifted further east towards New Zealand that maintained the ridge over most of the state. A surface trough parallel to the southern and central Queensland coast extended southwards with an embedded sub-tropical low pressure shifting southwards along the central and Capricornia coasts reaching the Sunshine Coast in the evening. An upper low pressure system lied over the central inland of the state, aiding with instability. This brought rainfall with heavy falls and dangerous seas along the southern coastal waters.
- A high pressure system shifted to over Tasmania that extended a ridge over the state on the 6th. A surface trough in the western Coral Sea lied parallel to the east Queensland coast while drifting southwards. A sub-tropical low embedded on the trough lied off the southern Queensland coast while shifting south-eastwards further offshore. An upper level low pressure system and trough over the inland shifted into the southeast in the evening with unstable conditions remaining in the region. Dangerous ocean conditions persisted along the southern Queensland coast.
- On the 7th a surface trough with an embedded low pressure system that lied offshore of the southern Queensland coast slowly moved away with conditions stabilising as rainfall easing over the east Queensland coast while persisting.
- A surface trough with an embedded low pressure system well offshore of the southern Queensland continued to shift eastwards away from the east Queensland coast on the 8th as a ridge of high pressure developed over most of the state. This extended some instability over the region.
- On the 9th a high pressure shifted further east to near New Zealand and extended a weakening ridge over the state. A surface trough in the Tasman and Cora Sea shifted further east well off the east Queensland coast.
- A weak ridge of high pressure extended over the state on the 10th. A surface trough shifted eastwards over the interior and extended a warm and stable airmass to its east.
- On the 11th a surface trough shifted eastwards across the east coast clearing the southeast in the morning, before contracting north-eastwards into central and northern Queensland coasts. A high pressure system in the Great Australian Bight extended a cooler and drier airmass in the wake of the trough from a strengthening ridge.
- A surface trough shifting northwards over the central and northern Queensland coasts and a high pressure system over southern Australia shifting into south-eastern Australia that extended a strengthening ridge across the state in the wake of the trough allowed a cooler and drier air mass to spread across southern Queensland on the 12th.
- A high pressure system over south-eastern Australia shifted east into the Tasman Sea on the 13th and extended a strengthening ridge along the east Queensland coast.
- On the 14th to 16th the ridge remained in place along the east Queensland coast as the high pressure system moved eastwards across the Tasman Sea.
- On the 17th a surface trough over central and southern inland of the state shifted into the southeast later in the day and brought some instability. A high pressure system in the Tasman Sea extended a weak ridge along the east Queensland coast.
- A high pressure system over southern Australia and in the Tasman Sea on the 18th extended a weak ridge over the state.
- On the 19th and 20th a high pressure system over southern Australia shifted eastwards into eastern Australia and maintained a weak ridge over the southern Queensland.
- A weak high pressure system in the Coral Sea extended a weak ridge over southern Australia on the 21st. A surface trough shifted eastwards over the south before shifting off the east Queensland coast in the evening.
- In the wake of the trough a high pressure system shifting eastwards over southern Australia on the 22nd and into the Great Australian Bight on the 23rd and 24th extended a ridge over southern Queensland on the 22nd and across the state on the 23rd and 24th.
- On the 25th a high pressure system over the Great Australian Bight extended a ridge over south and along the east Queensland coast.
- The high pressure system moved eastwards into south-eastern Australia on the 26th to 28th and extended a ridge along the east Queensland coast.
- On the 29th the high pressure system shifted eastwards into the Tasman Sea and extended a ridge along the east Queensland coast. Some instability as a result of moist onshore flow and an upper trough amplifying over southern Queensland.
- A high pressure system in the Tasman Sea maintained a ridge along the east Queensland coast with moist onshore winds. An upper trough amplified over southern Queensland while shifting eastwards. A weak coastal trough developed along the southern Queensland coast, with instability in the region.
Daily weather notes
- 1/4/21: Cloudy periods with Cu and Sc clouds. A moderate to heavy shower in the mid-afternoon with some light showers with some moderate falls later in the afternoon and light showers in the evening. Slightly warm from early in the day with the temperature falling a little slowly, eased to near average in the morning before the temperature became generally stable from the late morning as the maximum temperature was reached. The temperature was variable from the mid-morning to the mid-afternoon and eased from slightly cool in the early afternoon to briefly cold later in the afternoon while the temperature fell. In the evening, the temperature fell slowly that eased back to near average. Near average dew point fell slowly in the early hours, rose in the morning and in the afternoon before briefly rising more sharply in the mid-afternoon while remaining near average. After falling a little the dew point fell slowly later in the afternoon and in the evening close to average. Relative humidity was slightly below average or moderately low from early that rose slowly in the early hours. Relative humidity eased from moderately low to near average later in the morning as the relative humidity stopped falling later in the morning and then started to rise. In the afternoon, the relative humidity became very high that rose sharply for a brief period in the mid-afternoon, rose slowly during the rest of the afternoon and in the evening that gradually eased to slightly above average late in the evening. Light SSW to SSE winds from early with some SW winds before light S to SSW winds in the morning tended S to SE from the mid-morning, then SSW to SE in the afternoon and early in the evening with some E to SE winds, and mostly SSW to SSE winds later in the evening with calm winds at times.
- 2/4/21: Partly cloudy and cloudy at times. Light showers in the first half of the early hours and some very brief light showers in the evening. Slightly warm temperature in the early hours while the temperature slowly fell before easing back to near average in the morning and in the early afternoon that became slightly cool in the afternoon after the maximum temperature was reached in the early afternoon. From the mid-morning to the mid-afternoon the temperature was near average, and the temperature eased to near average later in the afternoon. In the evening, the temperature fell rather slowly and became slightly warm and then warm later in the evening. Dew point was near average that fell slowly in the early hours, rose a little in the morning before falling generally in the morning and afternoon that became briefly slightly below average in the mid-afternoon. After rising slightly in the late afternoon close to average, the dew point fell slightly before falling slightly in the evening. Relative humidity was near average early in the day and became generally slightly below average in the morning while the relative humidity fell. The relative humidity eased to near average in the afternoon after the relative humidity stabilised from the late morning. From the mid-afternoon the relative humidity was slightly below average and became moderately low in the evening as the relative humidity rose a little slowly. Light SSW to SSE winds in the early hours, S to SSW later in the early hours and in the early morning before light SSE to ESE winds from the morning becoming S to SSE in the evening.
- 3/4/21: Mostly cloudy with Cu and Sc clouds. Brief light showers in the early hours and in the early morning, light showers from the morning to the mid-afternoon with a light to moderate shower in the mid-afternoon and in the early evening. Stable temperature from early in the day and was warm before easing to near average in the morning with the temperature stable or rose slowly in the morning. From the mid-morning to the late afternoon the temperature was variable that generally fell from the mid-morning becoming cool from the late morning and rose a little in the afternoon. After the maximum temperature was reached the temperature rose a little before falling again from the late afternoon while easing back to near average in the evening. In the evening, the temperature was slightly warm while falling very slowly. Dew point was close to average that was nearly stable early in the day before rising in the morning and early afternoon that became slightly above average in the afternoon before becoming generally stable through to the evening remaining slightly above average. Relative humidity was low or moderately low in the early hours and early morning while slowly rising before generally rising in the morning while easing back to near average and became moderately high. Relative humidity rose and fell several times in the morning and afternoon that became high or very high from the late morning to the mid-afternoon with the relative humidity elevated during the day. In the evening, the relative humidity stabilised slightly above average. Light S to SSE winds early in the day before S to SSW later in the early hours. Light S to SE winds in the morning with some E to SE winds, SSE to ESE winds in the afternoon and early evening after SSW to SSE winds in the early afternoon before S to SW winds later in the evening before W to SW winds at the end of the day.
- 4/4/21: Cloudy with Cu and Ns clouds. Light showers tending to light rain periods from later in the early hours, easing in the evening. Stable or slowly rising temperature in the early hours that was slightly warm becoming warm later in the early hours, before rising in the morning and eased to near average in the early morning. During the morning as the temperature rose slowly in the morning the temperature cooled and became cool later in the morning and cold in the afternoon, as the temperature stabilised in the late morning and in the early afternoon. Afterwards the temperature fell slowly that eased to near average in the evening as the temperature rose slowly. Dew point rose very slowly in the early hours before rising in the morning slightly above average before stabilising from the late morning, fell from the afternoon and rose a little later in the evening. Relative humidity was stable and elevated close to average from early and became high during the morning as the relative humidity remained stable and elevated that became very high from later in the morning before easing back in the evening to slightly above average later in the evening. Light WSW to SSE winds from early with some calm winds at times before S to SE winds tending E to SE in the morning and afternoon, mostly SSE to ESE winds from the mid-afternoon before calm winds early in the evening. Following this was light E to SE winds and shifting to S to SE later in the evening with some E to SE winds.
- 5/4/21: Cloudy with Cu and Ns clouds. Intermittent drizzle and light rain from early, drizzle and light rain from morning and increasing to light to moderate falls later in the evening. The temperature was stable early in the day, then fell slightly later in the early hours while remaining warm. In the morning, the temperature rose slowly, and more slowly from later in the morning and became cool in the late morning before falling in the mid to late afternoon. In the evening, the temperature was near average that became slightly warm before becoming warm late in the evening as the temperature rose slightly after falling very slowly. Dew point was stable early in the day and moderately high before falling during the rest of the early hours and in the early morning slightly above average. In the morning and afternoon, the dew point rose slightly above average becoming moderately high in the afternoon. From the mid-afternoon the dew point fell a little that temporarily eased to slightly above average before returning to moderately high in the evening while rising slowly. Relative humidity was stable and elevated from early that was slightly above average, became high during in the morning and very high from the late morning to the late afternoon. In the evening, the relative humidity eased and became slightly above average in the late evening. Light S to SE winds early in the day with some E to SE winds, then S to SE winds until the early morning before S to SE winds from the morning. In the evening were S to SSE winds before tending SSE to ESE later in the evening.
- 6/4/21: Cloudy with Cu and Ns clouds. Light to moderate rain at the start of the day eased to light falls. Drizzle and light rain from the morning with some light to moderate falls in the evening. Slightly warm early in the day and became hot later in the early hours as the temperature fell slowly before rising slowly from later in the early hours. In the morning and early afternoon, the temperature rose slowly easing to near average in the morning, to slightly cool later in the morning and cool in the afternoon. During the rest of the afternoon and in the evening the temperature fell while easing to near average. Late in the evening the temperature rose slowly and was slightly warm. Moderately high dew point from early fell before rising and then stabilised in the morning. From the mid-morning the dew point rose slowly moderately high before falling from the early afternoon that eased to slightly above average from the mid-afternoon. Late in the evening the dew point stopped falling and rose slowly. Relative humidity was elevated and stable over the entire day that was slightly above average from early, became high from the mid-morning, very high from the late morning before easing from the late afternoon to slightly above average later in the evening. Light E to SSE winds early in the day, then ESE to SE later in the early morning before shifting WNW to WSW coinciding with a dip to the minimum air pressure and then backed to S to SE from the early morning with some ESE winds, S to SSE winds in the late afternoon before S to SSW winds early in the evening tending to S to SE later in the evening.
- 7/4/21: Cloud decreased during the morning and was partly cloudy and cloudy at times with Cu and Sc clouds. Drizzle and light rain at times cleared in the morning. Light showers in the late morning and in the afternoon with a shower in the mid-afternoon bringing brief moderate falls. Warm from early as the temperature fell slightly before stabilising later in the early hours and eased during the morning to near average from the mid-morning. The temperature was quite variable in the late morning and in the afternoon that rose and fell several times. In the mid-afternoon the temperature was temporarily slightly cool before easing to near average from the late afternoon as the temperature fell steadily. Dew point was slightly above average from early that became moderately high from later in the early hours with the dew point stable then falling slightly later in the early hours and rose slowly in the morning. Slightly above average dew point in the morning that rose became slightly above average or moderately high in the late morning and in the afternoon with the dew point a little variable but was generally stable. In the evening, the dew point fell that eased close to average late in the evening. Relative humidity was stable and elevated slightly above average from early that became moderately high or high from the mid-morning and in the afternoon with the relative humidity rather variable during this time. In the evening, the relative humidity was slightly above average. Light S to SSE winds early in the day was followed by S to SSW winds before briefly tending WSW to SSW and then SSE to SSW in the morning. Winds became S to SE from the mid-morning, then SSW to SSE later in the afternoon before mostly calm winds in the evening.
- 8/4/21: Partly cloudy with Cu and Sc. Brief light showers in the early to mid-afternoon. Nearly stable temperature in the early hours before rising in the morning and was slightly warm from early. From the mid-morning the temperature was near average or slightly warm at times. In the afternoon, the temperature temporarily fell before recovering slightly before falling from the late afternoon and more slowly later in the evening that was slightly warm or near average. Near average dew point became slightly above average later in the early hours that was stable before rising slowly in the morning and afternoon slightly above average before falling from the mid-afternoon that eased back to near average in the evening. Relative humidity was close to average in the early hours before becoming slightly below average in the morning, near average from the mid-morning and became slightly above average in the afternoon as the relative humidity rose from the early afternoon that eased back to near average from the late afternoon. Mostly calm winds early with some light and variable winds between WNW to S before S to SW winds early in the morning, light S to SW winds in the morning, SSW to SSE winds in the early afternoon became S to SE during the rest of the afternoon with some S to SW winds before mostly calm winds in the evening.
- 9/4/21: Sunny in the morning and mostly sunny in the afternoon with some Cu clouds. Near average temperature from early that warmed to slightly warm from the mid-morning and warm from the late morning as the temperature rose quickly in the morning and more slowly during the afternoon. Later in the afternoon and in the early evening the temperature fell quickly easing back to near average and fell steadily in the evening. Near average dew point fell slowly in the early hours, rose in the morning, generally fell from the late morning before briefly rising sharply in the early evening and fell slowly during the rest of the evening. Relative humidity rose slowly in the early hours and fell quickly in the morning close to average that became slightly below average in the late morning and in the afternoon while falling quickly. In the late afternoon and early evening, the relative humidity rose quickly that eased to near average from the early evening. Calm winds before light N to WNW winds later in the morning, shifted in the late morning to S to SW in the afternoon, then NW to WSW from the mid-afternoon that became calm in the evening.
- 10/4/21: Sunny. Close to average temperature from early fell steadily before rising quickly in the morning and after becoming hot from the mid-morning the temperature rose more slowly later in the morning and in the afternoon. In the evening, the temperature eased to slightly warm as the temperature steadily fell from the late afternoon. Near average dew point fell in the early hours, rose a little quickly early in the morning before generally falling from the mid-morning that became slightly below average from the late morning. In the afternoon, the dew point was stable, then fell slightly from the mid-afternoon, then eased back to near average in the evening that rose a little in the early evening before falling slowly during the remainder of the evening. From early the relative humidity was near average that rose slowly before falling quickly in the morning that became slightly below average in the morning and low later in the morning before stabilising from the late morning. In the evening, the relative humidity eased to moderately low and to slightly below average late in the evening while the relative humidity rose. Mostly calm winds early, then light WSW to NW later in the morning, NW to WSW in the afternoon, WNW to SSW later in the afternoon before mostly calm winds in the evening.
- 11/4/21: Partly cloudy with Cu, Sc and Ac clouds clearing in the afternoon and became sunny. The minimum temperature was reached half-way through the early hours before rising during the rest of the early hours with near average temperature becoming slightly warm in the early hours and early morning that eased to near average during the morning. The temperature became slightly warm from the late morning and in the afternoon. In the early evening, the temperature became warm with the temperature falling a little slowly, then fell more quickly in the late evening while returning to near average. Dew point slowly rose from early close to average before generally stable dew point from the mid-morning that was a little variable that became slightly below average. In the afternoon and early evening, the dew point fell that became moderately low from the mid-afternoon and low from the early evening. The dew point then fell more slowly before stabilising later in the evening while remaining low. Relative humidity was mostly slightly below average that rose slowly in the early hours and fell quickly in the morning that became moderately low from later in the morning, then more slowly in the afternoon that became low later in the afternoon. In the evening, the relative humidity became very low after the relative humidity became stable from the late afternoon before rising a little later in the evening. Mostly calm winds early before WSW to SSW in the morning, shifting to W to NW in the middle of the day, then became W to WSW during the afternoon and early evening before W to SW winds during the rest of the evening.
- 12/4/21: Sunny and mostly sunny in the afternoon with some Cu and Sc clouds. Near average temperature early in the day became slightly cool early in the day and cool later in the early hours and in the early morning. During the morning, the temperature eased to slightly cool before returning to cool in the afternoon after the maximum temperature was reached in the early afternoon and generally fell during the rest of the afternoon. In the early evening, the temperature eased back to near average before the temperature became slightly cool while the temperature fell. Later in the evening the temperature rose a little and was slightly cool. Dew point fell slowly at the start of the day before rising during the rest of the early hours and from the morning that was low, easing to moderately low from the late morning before stabilising in the mid to late afternoon that eased to slightly below average. In the evening, the dew point was slightly below average while falling very slowly. Relative humidity eased from very low to low later in the early hours as the relative humidity rose slowly during the early hours. Relative humidity eased from low in the morning to slightly below average from the early afternoon and to near average in the mid to late afternoon. This is as the relative humidity stopped falling from the mid-morning after falling from the early morning, became stable before rising in the afternoon. In the evening, the relative humidity was slightly below average or near average that rose before starting to fall later in the evening. Light W to SW winds at the start of the day before mostly calm winds during the rest of the early hours and in the early morning. Light SSW to SSE winds in the morning, SSW to ENE winds in the middle of the day before some W to SW winds before E to NE winds from the mid-afternoon until the early evening. Winds were then mostly calm during the rest of the evening.
- 13/4/21: Sunny becoming partly cloudy in the afternoon with Cu clouds. After rising a little at the start of the day the temperature stabilised before falling later in the early evening close to average. In the morning it was slightly cool though it was near average in the mid-morning with the temperature variable from the mid-morning to the mid-afternoon. In the afternoon and evening the temperature remained slightly cool becoming cool later in the evening. Dew point fell slowly from early slightly below average that became moderately low from the early morning and rose slowly in the morning and afternoon moderately low but was a little variable. From the late afternoon the dew point eased to slightly below average while falling slowly. Relative humidity was moderately low or slightly below average from early in the day while the relative humidity fell before rising later in the early hours. From the morning the relative humidity gradually eased from moderately low to slightly below average from the late morning to near average in the evening. Calm winds early with some W to SW winds or SSW to SSE winds before light S to SW winds in the morning that backed to E to SE with some E to NE winds in the late morning. In the afternoon were NE to SE winds, E to NE from the mid-afternoon before mostly calm winds in the evening.
- 14/4/21: Mostly sunny with some cu clouds. Cool from early in the day that eased to near average from the mid-morning and was variable that rose and fell several times from the mid-morning to the mid-afternoon. Later in the afternoon the temperature became slightly cool and after easing to near average in the early evening the temperature returned to slightly cool. Later in the evening the temperature fell slowly. Dew point fell slightly in the early hours, then rose in the morning that was slightly below average before stabilising from the mid-morning that eased back to near average from the mid-afternoon. Early in the evening the dew point was stable before falling slowly later in the evening. Relative humidity was near average from early becoming slightly below average from the morning and eased to near average after the relative humidity stopped falling and started to rise. Calm winds from early were followed by light SSE to SW winds in the morning, then variable later in the morning and in the middle of the day. Light NNW to ENE winds in the early afternoon, then NE to ESE winds in the mid-afternoon before N to ENE winds in the late afternoon before mostly calm winds in the evening.
- 15/4/21: Mostly sunny with some Cu clouds. The temperature was near average and stable early in the day before falling during the rest of the early hours and was slightly cool. Slightly cool temperature in the morning became near average from the mid-morning while the temperature rose. In the late morning and in the middle of the day the temperature fell slightly before rising in the afternoon that was near average and was slightly warm at times. From the mid-afternoon the temperature fell steadily close to average though was slightly warm early in the evening when the temperature temporarily fell a little slowly. Dew point fell slowly in the early hours that was near average at the start of the day that became slightly below average during the rest of the early hours. In the morning, the dew point rose, eased to near average, became generally stable in the mid-morning before falling from the late morning that became slightly below average in the mid-afternoon. In the mid-afternoon the dew point briefly rose sharply back to near average and was stable during the rest of the afternoon before falling slowly in the evening. Near average relative humidity from early in the day that became slightly below average from the late morning to the mid-afternoon while the relative humidity fell quickly in the morning. In the mid-afternoon the relative humidity rose sharply for a brief period before continuing to rise thereafter and was close to average but was slightly below average early in the evening. Near average relative humidity from early became slightly below average from the late morning to the mid-afternoon while the relative humidity fell quickly in the morning. In the mid-afternoon the relative humidity rose sharply for a brief period before continuing to rise thereafter and was close to average but was slightly below average early in the evening. Calm winds early, light, and variable winds at times in the morning, which became NNW to WSW and then SW to SE later in the morning, SSW to W in the early afternoon that was followed by SE to NE winds that veered to N to NW in the mid-afternoon. With the jump in the humidity the wind was then N to NE with some ENE winds, became N to NW in the evening before calm winds later in the evening.
- 16/4/21: Sunny becoming partly cloudy from the mid-afternoon with Cu clouds. Near average temperature from early in the day becoming slightly warm and then warm later in the morning. In the afternoon, the temperature was warm with the maximum temperature reached in the early afternoon before the temperature stabilised. From the mid-afternoon the temperature fell and eased to near average before the temperature falling more slowly in the evening and became warm. Dew point fell in the early hours before rising in the morning close to average, then fell in the late morning and in the early afternoon though was a little variable. In the afternoon, the dew point generally rose while remaining close to average becoming slightly above average in the late afternoon. From the late afternoon the dew point fell slowly close to average. Near average relative humidity from early, became slightly below average from the late morning as the relative humidity fell quickly in the morning and became moderately low in the afternoon. From the mid-afternoon the relative humidity rose that eased back to near average in the late afternoon. In the evening, the relative humidity was slightly below average and to moderately low later in the evening with the relative humidity stable from the early evening. Mostly calm winds early before light NE to NNW winds in the morning became SSW to ESE later in the morning, SSW to W winds in the early afternoon that backed during the afternoon to ENE to ESE in the mid-afternoon and E to SE from the late afternoon. Later in the evening were S to ESE winds.
- 17/4/21: Mostly cloudy with Cu, As and Ac clouds. A light shower late in the afternoon before a moderate to heavy shower in the early evening that was followed by some light showers during the rest of the evening. Warm early in the day while the temperature fell slowly before easing back to near average in the morning while the temperature rose before easing back to slightly cool from the mid-morning as the temperature rose more slowly from the late morning. From the late afternoon the temperature was near average that briefly rose sharply with the moderate to heavy shower. Dew point fell slowly in the early hours that stabilised later in the early hours and after rising slightly in the early morning the dew point stabilised before rising from the mid-morning close to average. In the mid-afternoon the dew point fell slightly, rose slightly in the late afternoon before generally falling in the evening close to average though was stable for a brief period late in the evening. Relative humidity was stable or rose slowly in the early hours moderately low before quickly returning to near average in the morning becoming slightly above average later in the morning and moderately high in the afternoon as the relative humidity fell a little slowly in the morning. The relative humidity became stable from the late morning and rose from later in the afternoon. Slightly above average relative humidity from the late afternoon became near average late in the evening. Light S to SE winds early in the day, then S to SW later in the early hours before calm winds early in the morning. Light SSW to SSE winds in the morning became light and variable later in the morning and in the early afternoon, S to ESE in the afternoon, SE to NE from the mid-afternoon and calm winds at times in the afternoon and in early evening. Early in the evening after the moderate to heavy shower were W to SSW winds that became S to SW before mostly SSW to SSE winds later in the evening with some calm winds.
- 18/4/21: Mostly sunny with some Cu and Sc clouds increasing a little in the afternoon. Near average temperature from early in the day and became cool from the morning that rose a little slowly in the morning. The temperature was variable in the afternoon while remaining slightly cool and remained slightly cool in the evening except for near average temperature in the early evening. Dew point fell in the early hours and in the morning close to average becoming slightly below average from the morning that generally rose slowly, then generally fell slowly in the afternoon that became near average in the early afternoon and slightly below average during the rest of the afternoon. Later in the afternoon the dew point briefly rose a little back to near average and became stable before falling in the evening slightly below average. Relative humidity was stable and near average in the early hours, slightly below or near average in the morning and near average from the mid-morning. Light WSW to SW winds at times with some calm winds in the early hours, calm winds later in the early hours before light S to SW winds in the morning with some W to SW winds and S to SE winds. Light WSW to SSE winds in the early afternoon was followed by W to SSW winds before backing in the mid-afternoon to E to NE later in the afternoon. In the late afternoon and evening winds were mostly calm.
- 19/4/21: Sunny and mostly sunny in the afternoon with Cu clouds. The temperature fell steadily in the early hours and was slightly cool before becoming cool in the morning before easing back to slightly cool during the morning and to near average from the mid-morning as the temperature rose. In the early afternoon, the temperature temporarily stopped rising and fell slightly and became slightly warm before rising again to the maximum temperature in the mid-afternoon. During the afternoon and evening the temperature was slightly cool while the temperature fell. Slightly below average dew point fell slowly from early, rose early in the morning before falling slowly from the mid-morning and became moderately low later in the morning. In the afternoon, the dew point rose slowly while easing back to near average before falling slowly in the evening. Early in the day the relative humidity rose slowly, then fell in the morning close to average becoming slightly below average and easing back to near average from the mid-afternoon. Mostly calm winds early, light ENE to SSE winds in the early morning, then light SSW to SSE winds in the morning, SSW to ESE winds in the late morning, then variable winds in the afternoon, NNE to ENE in the late afternoon before mostly calm winds in the evening.
- 20/4/21: Sunny in the morning and mostly sunny from the late morning. Slightly cool from early in the day with the temperature falling slowly and was stable at times. From the mid-morning the temperature eased back to near average and during the remainder of the day. The temperature was a little variable from the mid-morning to the mid-afternoon. Dew point fell slowly in the early hours slightly below average, then rose a little in the morning becoming near average before stabilising from the mid-morning. In the late morning and early afternoon, the dew point fell becoming slightly below average in the afternoon, rose in the afternoon and early evening easing back to near average from the late afternoon before rising slowly in the evening close to average. Near average relative humidity rose slowly in the early hours and in the early morning. Relative humidity became slightly below average from the morning that fell quickly in the morning before easing back to near average from the late afternoon after rising quickly later in the afternoon. Mostly calm winds early became NW to NNE winds in the morning with some SW to NW winds later in the morning, NW to NE winds in the afternoon and early evening before W to NW winds later in the evening with calm winds at times in the evening.
- 21/4/21: Sunny with some Cu clouds in the afternoon. Near average early became slightly cool in the morning as the temperature rose a little slowly before easing to near average and then to slightly warm from the mid-morning after the temperature rose a little quickly. In the afternoon and early in the early evening the temperature was warm before easing during the evening to slightly cool in the late evening while the temperature fell from the mid-evening. Dew point fell slowly in the early hours that was near average becoming slightly below average later in the early hours before rising in the morning close to average. From the mid-morning the dew point became stable and close to average, then fell in the afternoon becoming moderately low from the mid-afternoon to low in the late afternoon. In the evening, the dew point rose a little before becoming stable later in the evening while easing to moderately low. Relative humidity was near average or slightly below average from early that generally rose slowly before falling in the morning that was slightly below average in the morning that slipped from moderately low in the early afternoon to very low early in the evening as the relative humidity fell quickly in the morning and afternoon. In the evening, the relative humidity eased back to moderately low while the relative humidity rose. Calm winds at times with WNW to WSW winds early in the day tended to S to WSW and then NW later in the early hours and early in the morning. Light S to SW winds tended ENE to SSE and then tended N to ENE in the morning before shifting to W to NW from the mid-morning. In the afternoon were ENE to WSW winds, WSW to SW from the late afternoon before mostly calm winds later in the evening.
- 22/4/21: Cloudy with Cu, Sc and As clouds. Cool becoming cold in the early hours before remaining cool in the morning while the temperature rose in the morning before stabilising later in the morning. In the afternoon, the temperature became cold with stable temperature falling from the mid-afternoon. Early in the evening the temperature eased back to near average that temporarily rose before falling slowly. Later in the evening the temperature fell more quickly while remaining close to average. Dew point fell slowly in the early hours before rising from later in the early hours that was moderately low, then rose from later in the early hours, became stable from the morning and fell a little from the late morning. While remaining moderately low the dew point rose in the afternoon, briefly falling in the early evening before becoming stable during the rest of the evening moderately low. Moderately low relative humidity from early in the day that was slightly below average at times before becoming slightly below average from the morning. In the afternoon, the relative humidity eased to near average, fell sharply for a brief period in the early evening becoming low and became stable and then became very low before easing back to low while the relative humidity started to recover. Calm winds became WSW to NW in the morning that tended N to WNW in the afternoon with some variable winds before calm winds from the mid-afternoon. In the evening were SW to NW winds with calm winds and variable winds at times.
- 23/4/21: Sunny. The temperature eased from near average at the start of the day to cold in the early morning that eased during the morning to slightly cool from the mid-morning while the temperature rose and remained slightly cool until the mid-afternoon while the temperature continued to rise to the maximum temperature in the mid-afternoon. From later in the afternoon the temperature became cool while the temperature fell. Dew point was stable and moderately low before becoming low in the morning that generally rose from the mid-morning and then rose a little more quickly in the mid-afternoon while easing to moderately low. From the late afternoon the dew point fell while remaining moderately low. Relative humidity was low that generally rose slowly in the early hours, though the relative humidity fell for a brief period half-way through the early hours. As the relative humidity fell quickly in the morning the relative humidity remained low which after stabilising from the mid-morning the relative humidity eased to moderately low in the afternoon. From the late afternoon the relative humidity eased further to slightly below average as the relative humidity rose. Mostly calm winds with W to WSW winds and calm winds at times before S to SW winds in the morning with some SW to NW winds and became variable later in the morning and at times in the afternoon. In the early afternoon were NNE to E winds, followed by E to ENE winds and N to NE winds in the late afternoon and briefly at times in the evening with otherwise mostly calm winds.
- 24/4/21: Mostly sunny. Cool from early in the temperature that was temporarily cold in the early morning and was slightly cool from the mid-morning that became generally stable before rising a little in the afternoon before stabilising until the mid-afternoon. Moderately low dew point fell slowly in the early hours, then rose in the morning while easing to slightly below morning, rose more slowly from the mid-morning before falling slowly later in the morning and early in the afternoon. During the rest of the afternoon the dew point rose slowly before falling slowly in the evening slightly below average. Relative humidity was near average or slightly below average in the early hours and early morning and was slightly below average in the morning and afternoon that was near average in the late morning and from later in the afternoon. Calm winds early before light SE to SW winds in the morning, was followed by variable winds later in the morning, then NNW to NE with some E to NE winds, NNE to ENE later in the afternoon before calm winds in the evening.
- 25/4/21: Mostly sunny with some Cu clouds. Slightly cool early in the day became cool later in the early hours and in the early morning as the temperature fell a little more quickly later in the early hours after the temperature fell rather slowly early in the day. From later in the morning the temperature eased to near average before the temperature generally stabilised in the afternoon that was a little variable. From the late afternoon the temperature became slightly cool when the temperature fell during the rest of the afternoon and in the evening. Dew point fell slowly in the early hours, rose in the morning and more slowly from the mid-morning that eased from slightly below average to near average. The dew point fell from the late morning that became slightly below average and then moderately low in the afternoon. In the mid-afternoon the dew point rose sharply for a brief period while easing to slightly below average before becoming stable during the rest of the afternoon. In the evening, the dew point fell slowly slightly below average. Relative humidity was near average from early becoming slightly below average in the morning. After the relative humidity briefly rose sharply in the mid-afternoon and the relative humidity rose the relative humidity eased to near average from the mid-afternoon. Calm winds from early became SW to SE in the morning light SW to SE winds later in the morning with some NNE to SE winds, variable winds in the middle of the day were followed by mostly SSW to E winds, N to ENE in the late afternoon before calm winds in the evening.
- 26/4/21: Mostly sunny in morning and partly cloudy in afternoon with Cu and Sc clouds. The temperature was near average or slightly below average that was stable or fell slowly from early that became average in the mid-morning before became slightly cool from late morning and in the afternoon as the temperature rose more slowly in the late morning, reached the maximum temperature in the early afternoon, and became stable until the mid-afternoon. The temperature was variable from the late morning to the late afternoon. In the evening, the temperature was mostly near average that became stable or fell slowly later in the evening. The dew point fell slowly at the start of the day slightly below average which after the dew point briefly rose the dew point fell slowly during the rest of the early hours and in the early morning close to average. The dew point fell slowly from late in the morning that became slightly below average in the afternoon. In the evening, the dew point was stable and slightly below average becoming near average late in the evening. Near average relative humidity from early except for briefly slightly below average relative humidity in the early evening. Calm winds early before SSE to SW winds from early, light W to SSE winds in the morning became SSW to ESE later in the morning, which after some variable winds in the early afternoon became ESE to NE in the afternoon, E to NE from the mid-afternoon before winds became mostly calm in the evening.
- 27/4/21: Partly cloudy with Cu, Sc, and Ac clouds. The temperature was generally stable in the early hours after falling a little at the start of the day close to average becoming slightly cool in the morning and eased to near average from the mid-morning with the temperature rising from early in the morning. The temperature was variable from the mid-morning to late afternoon. After the maximum temperature was reached in the mid-afternoon the temperature became slightly cool easing to near average in the evening, though the temperature rose briefly half-way through the evening. Dew point was generally stable that rose and fell slightly at times close to average, rose slowly in the morning, fell from the late morning becoming slightly below average. After the dew point briefly rose sharply in the mid-afternoon the dew point generally fell slowly but was a little variable that was slightly below or near average becoming near average later in the evening. Relative humidity was near average at the start of the day that became slightly below average during the rest of the early hours and in the morning and became near average from the mid-morning. The relative humidity became slightly below average at times in the early afternoon, late afternoon, and early evening. Mostly calm winds with some variable winds late in the early hours and in the early morning. Light S to SSW winds in the morning became S to ESE from later in the morning, some S to SW winds in the afternoon, then ENE to NNE in the mid-afternoon that tended to E to ESE later in the afternoon and early evening. During the rest of the evening were calm winds.
- 28/4/21: Partly cloudy with Cu, Sc, and Ac clouds. Near average temperature from early that was temporarily slightly cool early in the day. From later in the early hours the temperature rose close to average before becoming slightly cool from the mid-morning and cool in the afternoon as variable temperature rose more slowly later in the morning and in the afternoon before the temperature fell later in the afternoon. Slightly cool early in the evening became near average with the temperature falling, though fell more quickly later in the evening. Near average dew point at the start of the day became slightly below average while falling and then rose from later in the early hours and eased to near average from the morning while rising slowly, becoming generally stable in the afternoon before falling slowly in the evening. Relative humidity was slightly below average that rose slowly in the early hours before starting to fall in the morning. Relative humidity eased back to near average from the mid-morning which after rising from the mid-afternoon became slightly above average or moderately high during the rest of the afternoon. In the evening, the relative humidity was near average or slightly below average. Mostly calm winds from early became light S to SSW in the morning. Light S to SSW winds in the morning became SSE to ESE later in the morning, E to SE from the early afternoon with some S to SE winds before becoming calm during the evening with some variable winds.
- 29/4/21: Partly cloudy with Cu, Sc, and Ac clouds. Near average from early became slightly cool in the morning while the temperature rose, which after the maximum temperature was reached in the early afternoon and the temperature fell and became cool. Variable temperature from the mid-morning to the mid-afternoon. From later in the afternoon the temperature eased becoming near average from early evening while the temperature fell. Dew point was near average that fell before rising from later in the early hours, then generally falling from the late morning before becoming generally stable from the mid-afternoon. Relative humidity was near average early and slightly below average relative humidity in the morning eased to near average from the mid-morning before becoming slightly above average in the afternoon as the relative humidity rose from the afternoon. In the evening, the relative humidity was near average. Calm winds early before S to SSW winds during the morning, becoming SSE to ESE later in the morning, E to SE in the afternoon and early evening before mostly calm winds during the rest of the evening with some S to SW winds late in the evening.
- 30/4/21: Partly cloudy and cloudy at times with Cu, Sc, As and Ac clouds. A light shower in the late morning, light to moderate thundery showers in the early afternoon before some light brief showers in the mid-afternoon and early evening. The temperature was stable in the early hours that was near average at the start of the day becoming slightly warm later in the early hours that eased to near average during the morning. Later in the morning the temperature cool further becoming cool as the temperature stopped rising and fell in the late morning. In the middle of the day and in the early afternoon the temperature rose to the maximum temperature before falling during the afternoon becoming cold. During the rest of the afternoon and evening the temperature fell slowly that eased to near average early in the evening before starting to rise a little late evening that became warm. Dew point fell slowly in the early hours before rising in the morning close to average, became stable in the afternoon, fell a little in the mid-afternoon, then became stable before falling slowly in the evening that started to rise late in the evening close to average. Relative humidity generally falling from the start of the day that was slightly below average and moderately low at times later in the early hours and in the morning. The relative humidity eased to near average in the morning that became high in the late morning as the relative humidity stopped falling and rose in the late morning. After temporarily falling the relative humidity rose in the early afternoon and became very high which eased to moderately high in the late afternoon and eased in the evening to near average late in the evening while rising slowly. Light S to SW winds with some calm winds in the early hours before WNW to SW winds became SSW to SE during the morning. Winds became SSE to E from the mid-morning, S to SE winds in the early afternoon backed to N to NE in the mid-afternoon that tended SW to SE during the rest of the afternoon and early evening. Light S to SW winds in the rest of the evening with some W to SW winds.
Station records for April 2021
NOTE: This is a summary of the aforementioned monthly records exceeded over a monthly basis. Additionally, it lists records that are the lowest or highest in at least 5 years. See end notes for more information about record periods.
Record low April mean daily maximum temperature in at least 5 years |
Observed [C] |
Most recent lower |
Years of record |
Monthly average |
26.5 |
26.1 in 2012 |
11 |
26.5 |
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Record low April minimum temperature |
Observed [C] |
Old record |
Years of record |
Monthly average |
9.1 on 23rd at 6:19 AM |
9.8 in 2015 on 27th at 6:10 AM |
11 |
16.1 |
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Record low April lowest daily maximum temperature in at least 5 years |
Observed [C] |
Most recent lower |
Years of record |
Monthly average |
21.7 on 4th at 1:23 PM |
18.9 in 2015 on 30th at 12:00 AM |
11 |
26.5 |
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Record low April minimum MSL pressure in at least 5 years |
Observed [hPa] |
Most recent lower |
Years of record |
Monthly average |
1004.6 on 10th at 3:21 PM |
1002 in 2011 on 14th at 2:58 PM |
11 |
1015.3 |
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Record high April maximum relative humidity |
Observed [%] |
Old record |
Years of record |
Monthly average |
99 on 6th at 4:33 AM |
= 99 in 2015 on 5th at 6:15 AM |
11 |
92 |
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Record low April daily maximum wind gust in at least 5 years |
Observed [km/hr] |
Most recent higher |
Years of record |
Monthly average |
35 on 5th at 8:00 PM |
19.4 in 2013 on 3rd at 3:17 PM |
11 |
20.1 |
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Record low April mean daily wind speed in at least 5 years |
Observed [km/hr] |
Most recent lower |
Years of record |
Monthly average |
10.7 |
8.9 Iin 2012 |
11 |
7.8 |
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Record high April total rainfall in at least 5 years |
Observed [mm] |
Most recent higher |
Years of record |
Monthly average |
130.1 |
133.2 in 2015 |
34 |
93.8 |
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Record high April highest daily rainfall total in at least 5 years |
Observed [mm] |
Most recent higher |
Years of record |
Monthly average |
53.8 on 6th |
55.2 in 2012 on 29th |
34 |
30.2 |
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Key records for April 2021
NOTE: These records are drawn from automatic data record for this site. See end notes for more information.
All time records |
No records |
Monthly records |
Minimum Temperature: 9.1 °C 23 Apr 2021 at 6:19 am |
Minimum Apparent Temperature: 7.8 °C 23 Apr 2021 at 6:42 am |
Minimum Wind Chill Temperature: 9.1 °C 23 Apr 2021 at 6:18 am |
Data summary tables for April 2021
Summary of Averages and Extremes for April 2021 for Ferny Grove, Brisbane, Queensland, Australia |
|
Min Temp |
Max Temp |
Mean Temp |
Temp Range |
Min Grass Temp |
Min Grass Temp Depression |
Min Relative Humidity |
Max Relative Humidity |
Mean Relative Humidity |
Min MSL pressure |
Max MSL Pressure |
Mean MSL Pressure |
Dew Point |
Max Wind Gust |
Max Wind Speed |
Daily rain |
Average |
14.7 |
26.5 |
20.6 |
11.8 |
13.0 |
1.6 |
51.8 |
95.3 |
73.6 |
1014.6 |
1018.7 |
1016.7 |
15.2 |
23.0 |
10.7 |
4.3 |
Min |
9.1 |
21.7 |
15.8 |
2.7 |
7.7 |
0.3 |
27 |
86 |
61 |
1004.6 |
1008.5 |
1006.6 |
4.2 |
14.0 |
6.0 |
|
Max |
20.4 |
33.7 |
24.4 |
18.6 |
19.9 |
3.1 |
93 |
99 |
96 |
1022.2 |
1025.7 |
1024.0 |
22.6 |
35.0 |
18.0 |
53.8 |
Total |
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130.1 |
Summary for April 2021 from long term average for Ferny Grove, Brisbane, Queensland, Australia |
|
Temperature |
Relative Humidity |
MSL Pressure |
Dew Point |
Wind Gust |
Wind Speed |
Rainfall |
Rainfall as Fraction of monthly average (%) |
Average |
-0.7 |
+0.1 |
-0.8 |
-1.2 |
+2.9 |
+2.9 |
+36.3 |
138.6 |
Min |
-1.4 |
-3.1 |
|
-1.8 |
|
|
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|
Max |
+0.0 |
+3.3 |
|
-0.6 |
|
|
+99.9 |
|
Monthly averages and extremes for Year of 2021 to Date for Ferny Grove, Brisbane, Queensland, Australia |
|
Temperature |
Temperature Anomaly from Long Term Avg. |
Rain total |
Rain Anomaly |
Rain days |
|
Avg Min |
Avg Max |
Low Min |
High Max |
Average |
Min |
Max |
Average |
|
|
|
Jan-21 |
20.0 |
29.9 |
16.6 |
36.6 |
24.9 |
-0.6 |
-0.8 |
-0.7 |
95.8 |
-49.2 |
19 |
Feb-21 |
20.3 |
30.4 |
17.3 |
36.1 |
25.3 |
-0.0 |
+0.4 |
+0.2 |
126.2 |
-35.6 |
14 |
Mar-21 |
19.4 |
28.7 |
14.8 |
34.6 |
24.0 |
+0.2 |
-0.0 |
+0.1 |
297.3 |
+173.1 |
17 |
Apr-21 |
14.7 |
26.5 |
9.1 |
33.7 |
20.6 |
-1.3 |
+0.0 |
-0.7 |
130.1 |
+36.3 |
9 |
YTD |
18.6 |
28.9 |
9.1 |
36.6 |
23.7 |
-0.5 |
-0.1 |
-0.3 |
649.4 |
+124.6 |
59 |
Min Temperature and time of occurrence for April 2021 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
16.7 |
17.4 |
19.3 |
19.0 |
19.6 |
20.4 |
19.2 |
17.6 |
15.7 |
15.1 |
16.9 |
11.1 |
12.6 |
11.4 |
12.9 |
14.4 |
5:55 A |
5:53 A |
5:44 A |
12:01 A |
9:36 A |
2:24 A |
3:46 A |
2:44 A |
5:52 A |
6:17 A |
1:48 A |
6:02 A |
6:24 A |
6:14 A |
5:55 A |
5:31 A |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
|
|
19.1 |
13.5 |
11.6 |
12.3 |
13.2 |
9.7 |
9.1 |
10.1 |
11.2 |
13.1 |
14.4 |
13.4 |
13.6 |
16.7 |
|
|
2:24 P |
6:54 A |
6:19 A |
5:53 A |
6:15 A |
5:39 A |
6:19 A |
6:12 A |
6:19 A |
6:21 A |
1:32 A |
3:56 A |
4:33 A |
6:26 A |
|
|
Max Temperature and time of occurrence for April 2021 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
26.1 |
26.6 |
23.4 |
21.7 |
22.5 |
23.2 |
27.7 |
29.3 |
31.2 |
33.7 |
29.5 |
25.3 |
25.2 |
26.5 |
29.1 |
30.7 |
11:00 A |
12:05 P |
12:20 P |
1:23 P |
2:06 P |
1:21 P |
1:28 P |
1:31 P |
3:18 P |
1:24 P |
2:24 P |
1:06 P |
2:05 P |
12:53 P |
2:18 P |
1:34 P |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
|
|
24.6 |
25.8 |
26.5 |
27.8 |
30.8 |
21.8 |
24.9 |
25.5 |
26.8 |
25.9 |
26.3 |
25.8 |
25.3 |
24.4 |
|
|
2:16 P |
1:54 P |
2:24 P |
1:48 A |
2:01 P |
12:29 P |
3:03 P |
1:10 P |
2:38 P |
12:59 P |
2:38 P |
1:56 P |
1:37 P |
1:00 P |
|
|
Daily Rainfall for April 2021 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
0.0 |
11.5 |
0.4 |
8.6 |
8.7 |
53.8 |
31.4 |
2.6 |
0.3 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
|
|
0.0 |
12.2 |
0.2 Dew |
0.2 Dew |
0.2 Dew |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
|
|
Temperature values coloured according to its difference from the long-term average for this month. Outlined value mark highest and lowest values.
Maximum temperatures are measured over the 24 hours from 9 am on the day of measurement. Minimum temperatures are measured over the 24 hours to 9 am of the day of measurement. This was previously different to the official time standards and measured in degrees ºC (before 2018).

Rainfall is measured over 24 hours to 9am and recorded on that day. This is the same as the official time standard and measured in millimetres. Some measurements are not made at 9am and is adjusted based on the automatic record. For other variables see Notes below.
Notes
Based on Bureau of Meteorology Climate summaries (Copyright) of which some data was obtained from. From September 2017 the Bureau of Meteorology Climate summaries were expanded to provide data from official stations in and near the Greater Brisbane “Greater capital city Statistical Area” (GCCSA).
Data Copyright Ferny Grove Weather 2021, Produced 16/8/21. Data Checking has been carried out, but errors may still be present and therefore there is no assurance of correctness. Corrections may be made at a later data if errors or deficiencies are found and/or improvements in data handling techniques are made, though data with major improvements may not be updated in this summary. Data measured with professional moderate accuracy equipment. This replaced non professional equipment of low accuracy with differences in the measured data. The new equipment measures the daily average wind speed and wind run about 40 % higher. Daily rainfall and grass minimum temperature is measured using non-professional equipment of moderate accuracy.
Site Commencement data is April 15 2009 except for daily rainfall which commenced on January 1 1987. Not all variables have been measured over the entire station record. Most variables are measured over a 24 hour period ending in the evening and over a 24 hour period from midnight effective October 5 2018. Maximum temperatures are measured over the 24 hours from 9 am on the day of measurement. Minimum temperatures are measured over the 24 hours to 9 am of the day of measurement. Rainfall is measured over 24 hours to 9am and recorded on that day. This is the same as the official time standard. Some rainfall measurements are not made at 9am and is adjusted based on the automatic record. Minimum Grass Temperature is measured over an approx. 12 hour period ending in the early morning. MSL refers to Mean Sea Level, which is the standard meteorological method of measuring air pressure reduced to sea level based on both elevation and temperature. Grass Minimum Depression is the difference of the grass minimum temperature from the air temperatures and is a positive value when the grass temperature is below the air temperature.
Up until March 9 2019 automatic records as Dew Point, Average Wind Speed, Dominant Wind Direction, Wind Run, Rain Rate and Hourly Rain are measured over a 24 hour period starting at midnight and recorded for that day. This started on the 6 October 2011. The automatic record is used for some data and also may be used if data is not available/ not suitable. From March 9 2019 the automatic record became the official record instead, simplifying this process. Until replaced on 5 October 2018 the temperature and humidity sensor is under exposed so minimum temperature and maximum humidity are incorrect and low accuracy rain gauge is used which are not used as the site’s official record. This data limitation does not apply to other measurements of temperatures, air pressure and humidity, wind gust, daily and monthly rainfall and rain days elsewhere in this summary which are recorded separately and form the official record for this site. The replacement equipment is sited in more exposed locations and therefore the limitations don’t apply, though the automatic daily rainfall doesn’t form the official data for the site.
Long term averages are based on all available long period past measurements from October 2019 whilst for non automatic rainfall is based on 1987 to 2017 average from the station record. Prior to this the long term average for Temperature, Relative Humidity and Air pressure is based on 2009 to 2015 average from the station record and wind speed is based on the 2010 to 2018 average from station record. Wind Run is 2011 to 2018 and Rain Rate and High Hourly Rain is 2011 to 2017.
The Fraction of monthly average expresses how much has fallen in respect to the long term average listed as a percentage. The decile ranking compares the rainfall total to the historical record for the site where the record is divided into 10 equal groups. Decile 1 is the lowest 10% of the record (10th percentile) and Decile 10 (90th percentile) is the highest 10% of the record. Decile 1 is considered “very low”, decile 2 and 3 “low”, decile 4 to 7 “average”, decile 8 and 9 “high” and decile 10 “very high”.