Western Australia in autumn 2020: a warm autumn; dry in the south

Autumn rainfall was below average for most of the southern two-thirds of Western Australia and in far north, while much of the southern Kimberley had a wet autumn. For the state as a whole, the mean temperature for autumn 2020 was the ninth-highest on record, as both the mean maximum and minimum temperature were among the top ten highest on record.

Below average rainfall for most of the southern two-thirds of WA

  • For Western Australia, autumn rainfall was 28% below average, largely due to very dry April
  • Several sites in the east Gascoyne and northern Goldfields recorded less than 30 mm seasonal rainfall totals, either their driest autumn on record or driest autumn since 1994
  • Ex-TC Esther produced significant rainfall in excess of 100 mm to 210 mm in the inland southern Kimberley and Northern Interior on 1 March, resulted in a number of highest autumn daily rainfall records
  • May was unseasonably wet in the Kimberley and Northern Interior, while it was a wet finish in the State's southwest and a once in a decade weather system impacted the western WA on the 24t hand 25th

Above average daytime temperatures for most of WA

  • The mean temperature was 1.16 °C above average, the ninth-warmest autumn on record for Western Australia
  • The mean maximum temperature was 1.43 °C above average, the tenth-warmest autumn on record for Western Australia
  • The mean minimum temperature was 0.89 °C above average for Western Australia, the equal tenth-highest on record for Western Australia
  • Mean minimum temperatures were in the mid-20s in the Pilbara coast and northwest offshore islands, the highest May mean minimum temperature on record
  • April was warm across the State; the state-wide mean maximum and minimum temperature were the fifth-highest and second-highest on record for April respectively
  • Mandora in the far southwest Kimberley coast recorded a late season high temperate record with 42.0 °C on 26 April, a first 42.0 °C in Australia post Anzac Day
  • A number of sites in the north Kimberley had their coldest autumn day on record on 21 May as a broad cloudband blanked the northern WA
  • Several sites in the Kimberley, Pilbara and the Southern Interior had their warmest autumn night on record in March and early April; Argyle Aerodrome's new autumn record of 31.1 °C on 2 April was also a national record

Further information

Media
(03) 9669 4057

Extremes in autumn 2020
Hottest day 45.1 °C at Onslow Airport on 1 Mar
Warmest days on average 36.9 °C at Marble Bar
Coolest days on average 21.2 °C at Shannon
Coldest day 10.9 °C at Manjimup on 25 May
Coldest night -1.5 °C at Eyre on 22 May
Coolest nights on average 9.7 °C at Wandering
Warmest nights on average 27.0 °C at Troughton Island
Warmest night 31.9 °C at Telfer Aero on 18 Mar
Warmest on average overall 29.8 °C at Wyndham Aero
Coolest on average overall 16.1 °C at Shannon
Wettest overall 330.2 mm at Wereroa
Wettest day 208.2 mm at Windjana Gorge on 1 Mar
Strongest wind gust 131 km/h at Cape Leeuwin on 25 May

Maps
ObservedAnomalyDecile rank
Total
rainfall
Map of Rainfall totals Map of Percentage of normal rainfall Map of Rainfall deciles
Mean
daily
maximum
temperatures
Map of Mean maximum temperature Map of Anomaly in mean maximum temperature Map of Decile rank of mean maximum temperature
Mean
daily
minimum
temperatures
Map of Mean minimum temperature Map of Anomaly in mean minimum temperature Map of Decile rank of mean minimum temperature

Click on a map to show it full size in a pop-up window


Record highest autumn daily rainfall
New record
(mm)
Old
record
Years of
record
Udialla 164.0 on 1 Mar 127.0 on 23 Apr 1973 63
Camballin 186.0 on 1 Mar 128.8 on 7 Mar 1969 50
Debesa 118.2 on 1 Mar 106.0 on 5 Mar 2000 22
Liveringa Station 141.0 on 1 Mar 106.4 on 7 Mar 2012 20



Record lowest autumn total rainfall
New record
(mm)
Old
record
Years of
record
Average for
autumn
Leinster Aero 8.2 10.4 in 2018 25 75.0

Lowest autumn total rainfall for at least 20 years
Observed
(mm)
Most recent
lower
Average for
autumn
Bulga Downs 8.2 4.4 in 1978 70.8
Bullfinch 27.0 4.0 in 1983* 82.7
Meekatharra Airport 13.8 6.4 in 1994 70.2
Mininer 19.2 0.0 in 1994 73.3

* note: there are gaps in the historical record at this site, so it is possible a lower value has gone unreported




Record highest autumn temperature
New record
(°C)
Old
record
Years of
record
Average for
autumn
Bidyadanga 44.0 on 25 Mar = 44.0 on 25 Mar 2016 62 34.6
Mount Elizabeth 37.6 on 30 Mar 37.1 on 22 Mar 2015 26 31.8



Record lowest autumn daily maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
autumn
Kununurra Aero 20.2 on 21 May 21.4 on 29 May 2004 35 34.7
Argyle Aerodrome 19.2 on 21 May 19.6 on 29 May 2004 26 34.3
Wyndham Aero 21.0 on 21 May = 21.0 on 29 May 2004 20 35.8



Record highest autumn daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
autumn
Telfer Aero 31.9 on 18 Mar 31.5 on 9 Mar 1992 46 20.1
Doongan 26.8 on 3 Apr 25.7 on 31 Mar 1989 32 18.6
Warburton Airfield 31.0 on 16 Mar = 31.0 on 11 Mar 1998 31 15.3
Argyle Aerodrome 31.1 on 2 Apr 30.4 on 22 Mar 2019 26 22.3
Kalumburu 27.5 on 3 Mar 27.3 on 2 Mar 2007 22 20.6
Wyndham Aero 29.9 on 3 Apr = 29.9 on 30 Mar 2016 20 22.8



Record highest autumn mean daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
autumn
Onslow Airport 23.2 = 23.2 in 2005 53 21.0
Thevenard Island 24.9 24.8 in 1996 23 23.9
Barrow Island Airport 25.0 = 25.0 in 2018 21 24.2
Varanus Island 26.6 26.5 in 2018 20 25.6



Summary statistics for autumn 2020
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
autumn
2020
Diff
from
average
Highest for
autumn
2020
Mean for
autumn
2020
Diff
from
average
Lowest for
autumn
2020
Total for
autumn
2020
Average
for
autumn
Rank of
autumn
2020
Fraction of
autumn
average
North Kimberley (district 01)
Kalumburu 35.2 +1.0 39.4 5 Apr 21.0 +0.4 10.9 25 May 152.0 253.5 average 60%
Mount Elizabeth 33.2 +1.4 37.6 30 Mar 17.4 +0.8 7.0 4 May 293.3 219.8 high 133%
Troughton Island 32.4 +0.4 34.5 1 May 27.0 +0.7 19.1 23 May 123.4 200.1 average 62%
Truscott 33.1 +0.3 36.8 30 Mar 24.0 +0.4 15.9 25 May 197.6 278.8 average 71%
Wyndham Aero 36.5 +0.7 41.5 29 Mar 23.2 +0.4 12.2 25 May 59.4 178.4 low 33%
East Kimberley (district 02)
Argyle Aerodrome 35.2 +0.9 41.5 4 Apr 23.3 +1.0 11.5 24 May 26.2 171.6 low 15%
Halls Creek Airport 33.6   40.0 30 Mar 18.8   7.6 23 May 113.4
Kununurra Aero 35.2 +0.5 40.4 4 Apr 21.0 -0.6 10.4 25 May 67.6 180.4 low 37%
Warmun 35.0 +0.5 41.5 4 Apr 21.1 +0.7 9.5 24 May 86.3 150.6 average 57%
West Kimberley (district 03)
Bidyadanga     44.0 25 Mar 23.1 +1.2 13.0 24 May 125.6 144.3 average 87%
Broome Airport 33.9 +0.6 41.1 23 Apr 23.7 +1.6 13.9 24 May 134.4 150.6 average 89%
Curtin Aero 35.7 +0.4 40.7 23 Apr 22.1 +0.2 14.4 23 May 95.6 201.5 low 47%
Cygnet Bay 33.3 +0.5 37.1 26 Mar 23.5 +1.4 15.4 5 May 183.7 240.8 average 76%
Derby Aero 35.3 +0.6 41.1 23 Apr 23.0 +0.7 14.2 25 May 221.8 172.5 high 129%
Yampi Sound (Defence) 35.8   41.3 23 Apr 21.6   9.8 24 May 273.2
De Grey (district 04)
Bedout Island 32.0 +0.3 37.5 25 Mar 26.7 +0.6 18.6 26 May
Karratha Aero 34.6 +1.0 42.2 29 Mar 23.8 +1.4 14.4 16 May 58.0 91.4 average 63%
Mandora 36.5 +1.4 44.4 25 Mar 21.6 +1.0 10.7 24 May 148.4 117.8 high 126%
Marble Bar 36.9 +1.7 43.8 30 Mar 22.1 +0.7 10.4 24 May 19.8 113.4 v low 17%
Pardoo Station 35.9 +1.2 43.8 26 Mar     9.5 28 May 84.6 101.9 average 83%
Port Hedland Airport 35.7 +1.4 43.6 26 Mar 22.5 +1.4 12.5 16 May 65.6 103.4 average 63%
Fortescue (district 05)
Barrow Island Airport 31.7 +0.9 39.3 8 Mar 25.0 +0.8 16.7 29 May 73.2 137.2 average 53%
Karijini North 34.5   41.4 28 Mar 21.7   8.2 28 May 71.8
Learmonth Airport 34.2 +1.4 42.8 1 Mar 20.4 +0.6 9.6 23 May 71.6 102.1 average 70%
Mardie 36.4 +1.4 43.5 29 Mar 23.1 +2.3 12.1 29 May 94.2 104.4 average 90%
Onslow Airport 34.9 +1.7 45.1 1 Mar 23.2 +2.2 12.5 28 May 55.4 129.0 average 43%
Thevenard Island 32.5 +0.8 40.1 27 Mar 24.9 +1.0 17.5 28 May 84.6 88.6 average 95%
West Gascoyne (district 06)
Carnarvon Airport 30.3 +1.2 41.6 23 Mar     9.2 23 May 17.2 61.9 low 28%
Denham 28.6 +0.1 41.4 24 Mar       8.4 63.6 v low 13%
Murchison 31.4 +0.6 40.5 11 Mar 15.8 -0.2 4.0 21 May 35.4 67.3 average 53%
Shark Bay Airport 31.1 +0.2 42.0 24 Mar 18.2 +0.2 7.6 23 May 4.0 47.8 low 8%
East Gascoyne (district 07)
Newman Aero 33.2 +1.6 40.3 20 Mar 18.4 +1.2 3.9 27 May 25.2 79.7 low 32%
Paraburdoo Aero 34.5 +1.2 41.1 27 Mar 20.5 +1.2 7.3 17 May 49.0 90.5 average 54%
Murchison (district 07A)
Meekatharra Airport 30.2 +1.0 40.3 11 Mar 17.3 +0.5 4.9 27 May 13.8 70.2 v low 20%
Mount Magnet Aero 29.1 +0.4 40.8 11 Mar 16.1 0.0 4.2 29 May 18.6 69.0 low 27%
Paynes Find 28.6 +0.4 42.0 11 Mar 14.0 0.0 1.7 20 May 24.4 85.5 v low 29%
North Coast (district 08)
Dalwallinu 26.7 -0.3 38.3 11 Mar 12.9 -0.2 2.7 19 May 54.6 71.1 average 77%
Geraldton Airport 28.5   40.1 10 Mar 16.2   9.3 17 May 40.8
Kalbarri 29.1 -0.3 39.5 24 Mar 16.7 +0.4 9.9 31 May 36.0 83.9 low 43%
Morawa Airport 28.6 -0.2 39.1 11 Mar 14.4 +0.1 5.4 22 May 45.6 69.0 average 66%
Mullewa 29.3 +0.5 39.3 10 Mar 15.7 +0.8 5.6 20 May 49.3 84.0 low 59%
North Island 26.5 +0.3 34.7 25 Mar 20.3 +0.1 10.3 14 May 52.4 61.7 average 85%
Wongan Hills 26.4 0.0 38.4 11 Mar 13.1 -0.1 3.4 19 May 51.8 93.7 low 55%
Central Coast (district 09)
Badgingarra Research Stn 26.7 -0.5 38.3 11 Apr 14.2 +0.7 6.6 19 May 0 108.3 lowest 0%
Bickley 23.3 -0.3 36.5 11 Apr 12.8 +0.4 6.1 9 May 242.6 210.5 average 115%
Garden Island HSF 24.2 +0.2 37.1 11 Apr 16.4 +0.3 7.6 15 May
Gingin Aero 26.8 +0.1 40.1 11 Apr 12.0 -0.1 0.7 21 May 71.6 119.5 low 60%
Gosnells City 26.4 -0.2 39.5 11 Apr     6.7 11 May 110.1 160.4 low 69%
Jandakot Aero 25.9 +0.1 39.2 11 Apr 13.2 +0.8 1.7 19 May 169.0 163.0 average 104%
Karnet 23.5 0.0 36.6 11 Apr 12.0 +0.3 3.3 19 May 209.5 230.1 average 91%
Lancelin 25.7 +0.1 36.0 26 Mar 15.1 +0.5 4.1 21 May 83.1 124.9 low 67%
Millendon (Swan Valley) 26.8   40.4 11 Apr 13.1   2.8 21 May 109.0
Pearce RAAF 27.3 +0.9 40.7 11 Apr 13.5 +0.1 1.7 21 May 99.8 133.2 low 75%
Perth Airport 26.4 +0.7 39.6 11 Apr 13.3 +0.2 2.3 19 May 149.6 153.2 average 98%
Perth Metro 26.0 +0.1 39.5 11 Apr 13.9 +0.2 4.6 19 May 157.6 142.6 average 111%
Rottnest Island 23.9 +0.3 35.2 11 Apr 17.3 +0.2 11.1 6 May 101.8 121.8 average 84%
Swanbourne 25.0 -0.4 37.3 11 Apr 15.7 +0.6 6.7 19 May 123.0 147.4 average 83%
South Coast (district 09A)
Albany Airport 22.4   34.5 8 Apr 12.0   2.3 10 May 208.0
Bridgetown 23.1 -0.3 34.2 25 Mar 10.3 +1.0 0.8 10 May 204.6 167.9 average 122%
Bunbury 24.0 -0.3 34.6 11 Apr 12.6 +0.9 2.5 9 May 173.2 153.1 average 113%
Busselton Aero 23.3 -0.8 34.5 8 Mar 12.1 +0.9 3.3 10 May 232.8 158.3 high 147%
Cape Leeuwin 21.6 +0.5 32.6 25 Mar 16.0 +0.7 10.2 6 May 204.0 223.8 average 91%
Cape Naturaliste 23.1 +1.2 31.6 24 Mar 14.6 +0.7 8.4 19 May 190.4 179.5 average 106%
Collie East 24.1 +0.1 36.4 11 Apr 9.9 +0.9 -0.6 10 May 188.4 151.5 high 124%
Donnybrook 24.4 +0.3 36.4 11 Apr       204.4 207.0 average 99%
Dwellingup 23.4 +0.7 36.7 11 Apr 11.3 +0.9 1.6 19 May 267.2 248.4 average 108%
Esperance 23.3 +0.3 36.8 12 Apr 13.5 +0.3 5.8 1 May
Esperance Aero 23.6 +0.3 36.9 12 Apr 12.8 +0.2 6.8 10 May 87.4 138.2 low 63%
Hopetoun North 23.1 -0.1 38.1 27 Mar 12.9 +0.4 5.5 10 May 106.4 111.2 average 96%
Jarrahwood 23.8 -0.1 34.5 11 Mar 10.1 +1.0 -0.5 10 May 214.4 195.0 average 110%
Mandurah 24.2 -0.1 35.2 9 Mar 16.1 +0.3 8.6 10 May 98.8 137.9 low 72%
Manjimup 22.1 +0.9 33.7 25 Mar 11.5 +0.8 4.4 9 May 230.8 217.6 average 106%
North Walpole 21.5 +0.1 33.9 8 Apr 13.0 +0.3 5.9 10 May 289.0 243.3 average 119%
Rocky Gully 22.0 +0.2 33.6 8 Apr 11.2 +0.4 3.0 10 May 213.6 164.7 high 130%
Shannon 21.2 -0.2 32.5 8 Apr 11.0 +0.3 2.3 10 May 275.4 227.1 high 121%
Witchcliffe 22.1 -0.5 32.0 9 Mar 12.4 +1.1 4.1 30 Apr 144.8 215.6 low 67%
North Central (district 10)
Bencubbin 25.5 -0.4 37.5 11 Mar 13.4 +0.6 3.5 9 May 41.3 81.3 low 51%
Cunderdin Airfield 26.7 +0.2 38.7 11 Apr 11.9 0.0 0.9 9 May 46.6 70.7 average 66%
Merredin 25.8 +0.3 37.0 11 Apr 13.4 +0.7 2.8 20 May 78.3 83.8 average 93%
Northam 26.8 +0.7 38.9 11 Apr 12.3 +0.4 2.2 10 May 54.8 96.0 low 57%
York 26.6 +0.3 39.0 11 Apr 11.0 +0.3 0.9 19 May 79.0 81.8 average 97%
South Central (district 10A)
Beverley 26.6 +0.4 38.8 11 Apr 11.5 +0.2 1.6 19 May 58.6 92.4 low 63%
Brookton 25.6 +0.6 37.5 11 Apr 11.2 +0.1 2.6 10 May 59.7 99.6 low 60%
Jacup 23.4 +0.6 35.2 9 Apr 10.7 +0.1 4.0 10 May 79.0 103.3 average 76%
Katanning 23.3 +0.1 35.4 11 Apr 11.3 +0.4 3.8 22 May 104.6 100.4 average 104%
Lake Grace 24.2 +0.1 36.2 11 Apr 11.8 +0.2 2.1 9 May 39.4 71.6 low 55%
Narrogin 24.0 +1.0 36.1 11 Apr 11.2 +0.7 2.8 10 May 80.2 112.2 low 71%
Newdegate Research Station 24.3 +0.2 36.4 11 Apr 10.1 +0.1 0.5 10 May 60.8 89.8 average 68%
Ravensthorpe 24.0 +0.5 35.5 9 Apr 13.4 +1.7 6.8 2 May 77.3 108.4 average 71%
Wagin 23.7 +0.1 35.5 11 Apr 11.4 +0.7 2.5 10 May 60.3 102.5 low 59%
Wandering 24.6 +0.1 37.6 11 Apr 9.7 +0.3 -0.4 29 Apr 100.4 99.5 average 101%
Eucla (district 11)
Balladonia 25.3 +0.6 37.2 12 Apr 10.9 0.0 1.4 23 May 49.8 74.3 average 67%
Eucla 23.9 +0.6 38.8 28 Mar 13.0 -0.3 4.3 31 May 72.6 79.9 average 91%
Eyre 24.8 +1.0 37.2 15 Mar 10.7 -1.0 -1.5 22 May 77.5 90.0 average 86%
Forrest 25.9 -0.1 40.0 14 Apr 11.5 -0.2 1.9 24 May 28.6 54.5 low 52%
Red Rocks Point 23.6 +0.4 36.3 28 Mar 13.7 -0.6 4.5 28 May 11.0 71.1 v low 15%
South East (district 12)
Bulga Downs 29.0 +0.5 40.1 11 Mar 13.5 -0.5 0.6 28 May 8.2 70.8 v low 12%
Kalgoorlie-Boulder Airport 26.0 +0.9 37.8 12 Mar 13.2 +0.7 2.5 27 May 8.0 69.8 v low 11%
Laverton Aero 27.9 +1.3 40.5 12 Mar 14.8 +0.2 0.9 28 May 13.4 72.7 v low 18%
Leinster Aero 28.8 +1.2 39.7 12 Mar 15.0 0.0 1.9 27 May 8.2 75.0 lowest 11%
Leonora Aero 28.2 +0.6 40.6 12 Mar 14.5 -0.2 2.0 28 May 31.4 67.8 low 46%
Munglinup West 23.9 0.0 35.7 27 Mar 11.9 +0.1 4.8 19 May 89.6 103.4 average 87%
Norseman Aero 25.5 +0.5 38.4 12 Apr 11.0 +0.3 0.0 30 Apr 50.8 73.0 low 70%
Salmon Gums Res.Stn. 24.3 +0.6 38.5 12 Apr 10.6 +0.7 -1.0 1 May 57.4 86.4 average 66%
Southern Cross Airfield 26.0 0.0 37.9 12 Apr 11.6 +0.1 0.4 9 May 27.8 83.6 low 33%
North East (district 13)
Carnegie 31.1 +1.1 41.4 12 Mar 15.9 +0.1 3.0 28 May 14.2 70.0 low 20%
Giles Meteorological Office 30.9 +1.8 40.6 19 Mar 17.5 +1.4 3.9 23 May 26.6 72.6 average 37%
Telfer Aero 35.6 +1.8 43.1 15 Mar 22.1 +2.0 10.1 24 May 39.2 106.5 low 37%
Warburton Airfield 31.2 +1.8 42.6 17 Mar 17.3 +2.0 5.4 21 May 20.4 63.5 low 32%
Wiluna Aero 30.0   40.1 12 Mar 15.4   0.7 28 May 11.8
Offshore Islands (district 200)
Adele Island 31.6   34.3 14 May 27.2   20.5 28 May
Browse Island 30.9   33.3 20 Mar 27.8   21.6 23 May
Varanus Island     37.6 28 Mar 26.6 +1.0 20.4 29 May 19.8 91.7 low 22%

Notes

The Seasonal climate summary, generally published on the first working day of each month, lists the main features of the weather in Western Australia using the most timely and accurate information available on the date of publication; it will generally not be updated. More extensive discussion of significant weather events, along with later information and data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review.

This statement has been prepared based on information available at 10 am on Monday 1 June 2020. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

In some situations, some or all of the rainfall is in the form of hail or snow. In these cases the totals given are for the water equivalent: the depth of liquid water that results from melting any frozen precipitation. There can be significant 'undercatch' of snow in strong winds, meaning the true precipitation can be higher than that reported.

Averages for individual sites are long-term means based on observations from all available years of record, which vary widely from site to site. They are not shown for sites with less than 10 years of record, as they cannot then be calculated reliably.
The median is sometimes more representative than the mean of long-term average rain.

The Rank indicates how rainfall this time compares with the climate record for the site, based on the decile ranking (very low rainfall is in decile 1, low in decile 2 or 3, average in decile 4 to 7, high in decile 8 or 9 and very high is in decile 10).
The Fraction of average shows how much rain has fallen this time as a percentage of the long-term mean.

Where temperature area averages are mentioned, they are derived from the ACORN-SAT dataset.

Further information

Media
(03) 9669 4057

Climate