Western Australia in December 2020: wet and cool in the north and east, warm in the west

It was very wet and cool December in the north and east of Western Australia as a result of passage of a number of tropical lows. Rainfall was below average in parts of the state's south although December is typically a dry month. Mean maximum temperatures were above average in the west of the state. Mean minimum temperatures were above average for much of the west and particularly warm along the Pilbara coast, in contrast to below average minima in the Kimberley and Northern Interior districts. For the state as a whole, it was the fourth-wettest December on record and coolest December overall since 2008.

Wet in the north and east

  • December rainfall was about twice (194%) the 1961-1990 average, and it was the fourth-wettest December on record for Western Australia.
  • Rainfall was well above average in the north and east of the state, due to a number of tropical lows; several sites in the Kimberley and Pilbara had their wettest December on record or wettest December for at least 20 years.
  • A tropical low (02U) crossed the Pilbara coast west of Port Headland on the 11th then tracked across the state's interior and southeast the following day, producing widespread moderate to heavy rainfall in excess of 50 mm, and up to 160 mm, along its passage.
  • Another tropical low (03U) crossed the west Kimberley coast on the 20th then tracked eastward through the Kimberley and into the Northern Territory; sites in the southeast Kimberley recorded the second wet spell of the month between the 20th and 24th, in addition to a wet spell between the 7th and 11th.

Daytime temperatures below average in the north and east, above average in the west

  • The mean temperature was 0.17 °C below the 1961-1990 average, the coolest December since 2008 for Western Australia.
  • Mean maximum temperatures were below average in the north and east of the state, including several sites in the Kimberley and Pillar either had their coolest December on record or coolest December for at least 20 years.
  • In contrast, mean maximum temperatures were above average in the west of the state, resulting in a statewide averaged mean maximum temperature of 0.54 °C below the 1961-1990 average, the lowest since 2007.
  • Mean minimum temperatures were below average in parts of the Kimberley and Northern Interior districts, in contrast to above average mean minima in much of the western half of the state, particularly along the Pilbara coast.
  • The statewide averaged mean minimum temperature was 0.18 °C below the 1961-1990 average, the lowest since 2008.
  • The first morning of the month was the coldest near the west coast, with overnight temperatures dipped to 2 °C, including several sites with their record low December temperature.
  • The tropical low (02U) brought unseasonably low maximum temperatures in the Kimberley and Pilbara with temperatures reached the mid-20s between the 8th and 11th, including a number of record low December maximum temperatures.
  • Carnarvon Airport recorded 45.6 °C on the 21st, its highest December temperature on record and the state's highest temperature of the month, however this was the lowest Western Australia highest December maximum temperature since December 2001.
  • Halls Creek Airport in the southeast Kimberley recorded a maximum temperature of 21.9 °C on the 22nd, which was one and a half degree lower than previous lowest December maximum temperature record, that was 23.6 °C recorded at the old Halls Creek Meteorolocal Office site in 14 December 1971.
  • It was a scorching Christmas Day in the state's southwest, with temperatures at numerous locations over 40 °C; several sites around Perth and the adjacent Central Wheat Belt district recorded 3 consecutive days of 40 °C between 23rd and 25th, and Mora Airport and Mullewa in the Central West district had 5 consecutive days of 40 °C.

Further information

Media
(03) 9669 4057

Extremes in December 2020
Hottest day 45.6 °C at Carnarvon Airport on the 21st
Warmest days on average 40.0 °C at Paraburdoo Aero
Coolest days on average 21.1 °C at Albany
Coldest day 16.2 °C at Shannon on the 1st
Coldest night 1.4 °C at Eyre on the 2nd
Coolest nights on average 10.8 °C at Jacup
10.8 °C at Rocky Gully
Warmest nights on average 27.0 °C at Bedout Island
Warmest night 30.7 °C at Telfer Aero on the 17th
Warmest on average overall 32.7 °C at Paraburdoo Aero
Coolest on average overall 17.0 °C at Windy Harbour
Wettest overall 695.6 mm at Cygnet Bay
Wettest day 191.0 mm at Cygnet Bay on the 21st
Strongest wind gust 135 km/h at Troughton Island on the 15th

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 December daily rainfall
New record
(mm)
Old
record
Years of
record
Warburton Airfield 83.0 on the 12th 60.7 on the 31st in 1947 62
Tjukayirla 74.2 on the 12th 49.0 on the 17th in 2007 21
Varanus Island 67.6 on the 11th 15.6 on the 31st in 2013 21



Record highest December total rainfall
New record
(mm)
Old
record
Years of
record
Average for
December
Ruby Plains 331.4 243.5 in 1930 77 79.7
Derby Aero 436.8 350.6 in 2016 66 83.4
Mount Amhurst 306.8 270.6 in 1930 65 79.8
Cygnet Bay 695.6 621.7 in 2017 55 98.8
Flora Valley 341.0 204.0 in 1998 43 100.4
Port Smith 552.2 512.6 in 2016 42 75.5
Sophie Downs 305.2 215.0 in 1999 37 99.6
Curtin Aero 343.0 337.2 in 2016 27 155.3
Billiluna 309.8 211.0 in 1998 26 85.1
Marble Bar 199.4 122.8 in 2013 21 37.7
Varanus Island 72.6 24.8 in 2010 21 5.8
Mount Winifred 330.8 237.4 in 2016 20 116.2

Highest December total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Average for
December
Sturt Creek 254.0 292.4 in 1906* 66.4
Meda 308.4 396.2 in 1920* 90.1
Bonney Downs 212.8 296.0 in 1975 35.1
Indee 152.0 367.0 in 1975* 24.5
Gibb River 331.0 354.0 in 1987 126.2
Mardie 89.8 171.3 in 1988 9.4
Mundrabilla Station 107.6 165.4 in 1994 19.7
Red Hill 85.9 111.6 in 1998 22.0
Coolawanyah 169.8 238.6 in 1999 36.7
Emu Creek Station 100.1 106.3 in 1998* 14.0
Mount Florance 170.8 274.2 in 1999* 32.5

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

 



Record highest December temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Carnarvon Airport 45.6 on the 21st 45.4 on the 27th in 1976 75 29.4
Denham 44.1 on the 21st 42.8 on the 23rd in 2018 33 29.3
Windy Harbour 36.2 on the 10th = 36.2 on the 27th in 2000 33 21.9



Record lowest December daily maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Telfer Aero 24.8 on the 9th 25.0 on the 17th in 1993 47 40.4
Cygnet Bay 26.0 on the 8th 26.9 on the 15th in 1993 35 34.9
Derby Aero 26.2 on the 9th 26.4 on the 18th in 2009 35 37.3
Curtin Aero 25.2 on the 9th 25.4 on the 27th in 2017 30 38.5
Marble Bar 27.6 on the 11th 27.8 on the 30th in 2013 21 42.0



Record lowest December mean daily maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Derby Aero 34.4 34.7 in 1998 34 37.3
Kununurra Aero 34.9 35.0 in 1998 34 37.4
Curtin Aero 35.2 35.5 in 1998 29 38.5
Fitzroy Crossing Aero 35.2 36.1 in 1998 23 39.4
Marble Bar 38.9 39.8 in 2001 20 42.0
Wyndham Aero 35.5 35.9 in 2008 20 38.2

Lowest December mean daily maximum temperature for at least 20 years
Observed
(°C)
Most recent
lower
Average for
December
Telfer Aero 37.8 36.5 in 1995 40.4
Doongan 32.6 32.0 in 2000 34.6
Kalumburu 33.6 33.5 in 2000 35.6
Troughton Island 32.0 31.5 in 2000 33.0
Warmun 36.2 35.6 in 2000 38.4

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




Record lowest December temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Brookton 3.0 on the 1st = 3.0 on the 13th in 1984 54 13.5
Wongan Hills 6.8 on the 1st 7.3 on the 2nd in 1998 54 15.8
Pingelly 4.5 on the 1st = 4.5 on the 10th in 1984 49 13.9
Goomalling 5.5 on the 1st 6.6 on the 6th in 2007 41 14.9
Gosnells City 8.0 on the 1st = 8.0 on the 2nd in 2002 29 16.4
Perth Metro 6.6 on the 1st 7.9 on the 7th in 2007 27 16.4
Gingin Aero 2.2 on the 1st 4.4 on the 7th in 2007 25 14.4
Lake Grace 5.2 on the 1st 6.0 on the 1st in 2005 24 13.6



Record lowest December mean daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Windy Harbour 11.1 11.2 in 2001 32 13.0

Lowest December mean daily minimum temperature for at least 20 years
Observed
(°C)
Most recent
lower
Average for
December
Bidyadanga 25.1 25.0 in 1994* 25.9
Derby Aero 25.5 =25.5 in 1995 26.4

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




Record lowest December mean temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Derby Aero 30.0 30.2 in 1998 34 31.8
Curtin Aero 30.0 30.1 in 1998 29 31.8
Fitzroy Crossing Aero 30.0 30.6 in 1998 23 32.6
Wyndham Aero 30.7 30.9 in 2015 20 32.5

Lowest December mean temperature for at least 20 years
Observed
(°C)
Most recent
lower
Average for
December
Kununurra Aero 30.0 29.9 in 1996 31.4
Carnegie 28.2 27.6 in 1999 30.0
Doongan 27.7 27.5 in 2000 28.9
Telfer Aero 31.7 =31.7 in 2000 33.0
Troughton Island 29.3 29.2 in 2000 30.2



Summary statistics for December 2020
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
December
2020
Diff
from
average
Highest for
December
2020
Mean for
December
2020
Diff
from
average
Lowest for
December
2020
Total for
December
2020
Average
for
December
Rank of
December
2020
Fraction of
December
average
North Kimberley (district 01)
Doongan 32.6 -2.0 36.0 4th 22.8 -0.4 20.0 1st 93.8 216.1 low 43%
Kalumburu 33.6 -2.0 37.4 16th 24.7 -0.3 22.8 16th 348.0 233.4 high 149%
Mount Elizabeth 32.3 -2.0 36.8 17th     17.5 23rd 353.7 172.3 v high 205%
Troughton Island 32.0 -1.0 33.9 1st 26.6 -0.8 22.7 16th 359.0 124.8 high 288%
Truscott 32.6 -1.7 36.3 1st 25.0 -1.2 22.1 16th 328.8 192.7 high 171%
Wyndham Aero 35.5 -2.7 41.8 16th 25.8 -0.9 23.3 9th 203.2 150.0 high 135%
East Kimberley (district 02)
Argyle Aerodrome 36.0 -1.6 41.9 16th 25.7 -0.4 22.4 23rd 196.0 135.5 high 145%
Halls Creek Airport 33.9   39.9 17th 23.8   18.9 22nd 250.2
Kununurra Aero 34.9 -2.5 40.0 16th 25.0 -0.5 23.0 4th 294.0 142.6 v high 206%
Warmun 36.2 -2.2 42.0 16th 25.6 +0.4 22.0 23rd 189.6 119.6 high 159%
West Kimberley (district 03)
Bidyadanga 34.5 -0.5 39.0 2nd 25.1 -0.8 22.5 6th 285.6 60.2 v high 474%
Broome Airport 33.3 -0.6 37.7 3rd 26.1 -0.5 23.4 11th 220.4 64.3 v high 343%
Curtin Aero 35.2 -3.3 40.8 1st 24.8 -0.4 22.5 13th 343.0 155.3 highest 221%
Cygnet Bay 31.5 -3.4 35.7 1st 25.5 -0.1 23.5 22nd 695.6 98.8 highest 704%
Derby Aero 34.4 -2.9 39.7 1st 25.5 -0.9 23.1 9th 436.8 83.4 highest 524%
Fitzroy Crossing Aero 35.2 -4.2 41.1 5th 24.8 -1.0 20.4 22nd 222.6 138.1 high 161%
Yampi Sound (Defence) 34.4   40.1 5th 24.8   22.4 23rd 594.2
De Grey (district 04)
Bedout Island 33.0 -0.5 34.7 31st 27.0 -0.2 24.6 10th
Karratha Aero 36.0 +0.1 43.8 19th 26.4 +0.8 20.6 11th 88.8 15.0 v high 592%
Legendre Island 32.4 0.0 35.2 23rd 26.8 +0.9 20.9 11th
Mandora 36.2 -0.6 41.2 4th 25.4 +0.9 20.5 24th 65.8 33.6 high 196%
Marble Bar 38.9 -3.1 43.5 19th 25.6 -0.6 21.5 11th 199.4 37.7 highest 529%
Port Hedland Airport 36.5 -0.2 42.1 1st 25.9 +1.7 21.9 11th 94.2 19.4 v high 486%
Roebourne Aero 37.8 -1.7 43.0 19th 25.5 +0.6 20.6 11th 81.4 16.2 v high 502%
Fortescue (district 05)
Barrow Island Airport 33.5 +1.1 38.7 5th 25.5 +1.0 21.5 14th 39.6 6.7 v high 591%
Karijini North 37.6   42.4 19th 24.5   18.7 11th 141.8
Learmonth Airport 38.1 +1.1 43.7 6th 22.1 +1.2 17.1 1st 15.2 6.1 v high 249%
Mardie 37.2 -0.4 42.1 19th 25.5 +2.4 20.4 11th 89.8 9.4 v high 955%
Onslow Airport 36.7 +0.7 42.3 5th 24.8 +2.4 22.0 14th 7.8 3.3 v high 236%
Thevenard Island 33.7 +1.5 39.1 5th 25.4 +1.6 23.4 1st 5.0 6.9 high 72%
West Gascoyne (district 06)
Carnarvon Airport 31.5 +2.1 45.6 21st 21.6 +0.9 16.0 1st 0 5.3 lowest 0%
Denham 30.7 +1.4 44.1 21st 20.6 0.0 14.0 1st 0.4 2.2 average 18%
Murchison 38.9 +1.4 44.0 3rd 22.1 +1.8 14.0 1st 27.2 13.5 high 201%
Shark Bay Airport 33.4 +1.0 44.7 28th 20.2 +0.5 14.2 1st 0.2 8.1 average 2%
East Gascoyne (district 07)
Newman Aero 37.2 -2.1 41.9 17th 24.5 +0.4 18.9 10th 54.2 35.3 high 154%
Paraburdoo Aero 40.0 -0.6 45.2 20th 25.4 +0.7 19.6 8th 39.8 26.4 high 151%
Murchison (district 07A)
Meekatharra Airport 37.8 +1.2 42.3 19th 23.2 +1.0 15.6 1st 19.8 14.5 high 137%
Mount Magnet Aero 37.4 +1.4 43.6 3rd 22.0 +0.7 12.4 1st 8.4 19.0 average 44%
Paynes Find 36.5 +1.4 42.5 25th 20.1 +1.6 10.6 1st 18.0 12.3 high 146%
North Coast (district 08)
Dalwallinu 34.3 +0.9 42.4 25th 16.4 +0.6 6.6 1st 1.2 11.8 low 10%
Geraldton Airport 32.7   43.5 23rd 17.1   9.8 1st 0.2 5.3 low 4%
Kalbarri 31.9 +0.7 42.7 22nd 18.6 +1.0 12.6 1st 0 3.8 lowest 0%
Morawa Airport 36.9 +1.5 43.7 25th 18.2 +0.7 8.2 1st 1.2 14.0 low 9%
Mullewa 36.9 +2.4 43.4 25th 19.0 +1.9 9.9 1st 8.8 8.5 average 104%
North Island 27.1 +0.5 34.9 23rd 20.2 +0.2 16.6 24th 0.2 4.0 average 5%
Wongan Hills 35.1 +2.5 42.7 25th 16.1 +0.3 6.8 1st 1.0 9.8 average 10%
Central Coast (district 09)
Badgingarra Research Stn 34.1 +2.0 43.0 25th 16.2 +1.1 6.8 1st 0 8.8 lowest 0%
Bickley 30.0 +1.8 39.1 25th 14.3 +0.5 6.5 1st 10.6 14.5 average 73%
Garden Island HSF 27.7 +2.2 38.7 24th 17.8 +0.5 11.2 1st 0.2 9.9 lowest 2%
Gingin Aero 33.1 +2.3 42.8 24th 15.3 +0.9 2.2 1st
Gosnells City 32.6 +2.1 40.5 23rd 17.3 +0.9 8.0 1st 7.4 11.3 average 65%
Jandakot Aero 31.6 +2.4 41.2 24th 16.2 +1.4 5.0 1st 2.2 10.4 average 21%
Jurien Bay 30.6 +2.3 40.0 29th 16.7 +1.1 8.4 1st 1.2 6.4 average 19%
Karnet 30.0 +1.8 38.6 25th 14.3 +0.8 4.8 1st 4.8 18.6 low 26%
Lancelin 29.5 +2.2 39.7 23rd 16.1 -0.1 9.2 1st 1.0 8.3 low 12%
Millendon (Swan Valley) 32.8   42.2 24th 16.3   6.2 1st 2.0
Pearce RAAF 33.4 +2.9 42.6 24th 16.7 +2.1 5.4 1st
Perth Airport 32.4 +3.3 41.7 24th 16.4 +1.4 4.9 1st 4.0 11.1 average 36%
Perth Metro 31.7 +2.4 41.1 24th 16.9 +0.5 6.6 1st 4.4 10.4 average 42%
Rottnest Island 26.5 +1.4 37.7 23rd 17.9 +0.2 12.8 1st 1.4 10.5 low 13%
Swanbourne 29.1 +1.2 39.7 23rd 17.6 +1.0 9.0 1st 2.8 10.9 average 26%
South Coast (district 09A)
Albany 21.1 -0.7 30.7 11th 15.0 +0.9 10.0 2nd 24.4 30.1 average 81%
Albany Airport 22.9   31.7 11th 12.3   6.0 15th 25.8
Bridgetown 28.4 +0.7 38.0 24th 11.6 +0.6 3.9 15th 2.4 18.2 low 13%
Bunbury 29.3 +1.9 37.9 30th 13.8 +0.3 5.5 1st 5.0 16.6 average 30%
Busselton Aero 29.5 +1.4 37.6 30th 13.0 +0.6 6.1 14th 2.4 10.1 average 24%
Cape Leeuwin 22.6 +0.8 30.1 24th 16.1 +0.3 11.3 2nd 5.0 20.5 low 24%
Cape Naturaliste 27.5 +3.8 35.5 23rd 14.2 +0.2 9.3 2nd 4.0 13.4 average 30%
Collie East 30.3 +1.5 39.0 24th 11.7 +0.2 5.1 1st 3.0 19.9 low 15%
Donnybrook 29.9 +1.6 38.5 24th       34.0 16.5 high 206%
Dwellingup 30.3 +2.9 39.2 24th 13.5 +0.9 4.4 1st 7.2 20.6 average 35%
Esperance 24.8 +0.1 42.0 25th 13.8 -0.6 8.6 2nd 7.4 19.8 low 37%
Esperance Aero 26.3 +0.3 42.8 25th 12.7 -0.8 8.2 1st 11.2 21.9 low 51%
Hopetoun North 23.4 -0.7 34.8 24th 14.1 +0.3 8.1 2nd 8.2 23.3 average 35%
Jarrahwood 28.8 +1.5 36.5 24th 11.9 +0.8 4.5 2nd 39.0 17.5 high 223%
Manjimup 27.3 +2.3 35.5 23rd 11.3 -0.4 6.9 1st 16.6 25.3 average 66%
North Walpole 23.3 +0.7 33.0 11th 12.7 -0.1 7.1 15th 25.2 41.9 average 60%
Rocky Gully 25.7 0.0 34.7 23rd 10.8 -0.2 5.8 15th 32.8 29.4 average 112%
Shannon 25.0 +0.5 34.2 23rd 11.4 +0.1 5.7 15th 30.6 32.0 average 96%
Windy Harbour 23.2 +1.3 36.2 10th 11.1 -1.9 8.5 16th 9.4 28.0 low 34%
Witchcliffe 26.2 +1.3 36.7 10th 12.5 +0.1 6.4 2nd 4.0 17.9 low 22%
North Central (district 10)
Bencubbin 33.1 +0.6 41.0 25th 16.5 +0.5 7.8 1st 5.5 13.4 average 41%
Cunderdin Airfield 34.1 +1.0 43.7 25th 15.1 +0.2 2.9 1st 0 8.1 lowest 0%
Merredin 33.3 +1.1 41.6 25th 16.5 +0.6 8.0 1st 13.2 14.0 average 94%
Northam 33.5 +1.3 43.8 25th 15.8 +0.5 5.5 1st 3.5 9.2 average 38%
York 33.7 +1.3 43.2 25th 14.2 +0.2 3.0 1st 1.2 11.8 low 10%
South Central (district 10A)
Beverley 34.3 +2.0 43.6 25th 14.8 +0.4 8.4 14th 0.6 10.4 low 6%
Brookton 32.6 +1.5 42.5 25th 14.1 +0.6 3.0 1st 0.1 10.3 low 1%
Hyden 32.4 +0.4 43.5 25th 13.7 -0.2 4.0 1st 10.8 14.4 average 75%
Jacup 26.7 +0.2 41.8 25th 10.8 -0.7 4.1 1st 13.8 27.5 average 50%
Katanning 29.0 +0.2 40.0 24th 11.3 -0.5 5.7 1st 1.2 24.0 low 5%
Lake Grace 30.2 +0.6 41.6 25th 13.4 -0.2 5.2 1st 0.2 20.4 lowest 1%
Narembeen 33.3 +1.2 42.7 25th 15.3 +0.8 6.8 15th 23.0 12.9 high 178%
Narrogin 30.5 +1.5 40.1 25th 13.3 +0.9 4.0 1st 0 14.0 lowest 0%
Newdegate Research Station 30.4 +0.7 42.3 25th 12.1 +0.4 4.2 1st 9.6 15.2 average 63%
Pingelly 30.9 +0.7 41.4 25th 14.1 +0.2 4.5 1st 1.4 12.6 average 11%
Ravensthorpe 27.2 -0.1 40.8 25th 12.7 -0.1 7.0 1st 4.6 23.7 low 19%
Wagin 29.4 0.0 40.4 24th 12.8 -0.2 4.6 1st 0.4 13.2 low 3%
Wandering 31.7 +1.2 42.0 25th 12.4 +0.3 2.3 1st 0.2 17.2 v low 1%
Eucla (district 11)
Eucla 25.5 +0.6 44.4 4th 15.6 +0.4 9.9 2nd 30.0 18.8 high 160%
Eyre 27.0 +1.2 43.6 4th 12.9 -1.2 1.4 2nd 27.7 21.0 high 132%
Forrest 29.1 -2.7 44.2 4th 14.0 -1.1 8.5 2nd 45.0 25.8 high 174%
Red Rocks Point 26.7 +1.9 44.9 26th 16.2 -0.3 9.7 2nd
South East (district 12)
Bulga Downs 36.1 -0.2 43.1 26th 19.9 -0.4 12.0 1st 2.4 12.8 average 19%
Kalgoorlie-Boulder Airport 31.7 -0.4 42.8 26th 17.3 +0.6 9.0 1st 4.4 16.3 low 27%
Laverton Aero 33.1 -0.9 41.9 26th 19.2 -0.7 13.7 28th 17.4 28.4 average 61%
Leinster Aero 35.6 -0.1 41.9 3rd 20.7 -0.6 14.5 1st 3.4 24.6 low 14%
Leonora Aero 34.3 -1.3 43.5 26th 20.2 -0.9 14.3 1st 3.2 16.0 low 20%
Munglinup West 27.8 +0.1 41.9 25th 12.2 -0.5 7.4 1st 3.4 25.5 low 13%
Norseman Aero 30.9 -0.4 40.3 25th 13.4 -0.7 4.0 1st 1.8 20.3 low 9%
Salmon Gums Res.Stn. 29.3 +0.2 41.6 25th 11.5 -0.7 3.8 28th 4.0 19.5 low 21%
Southern Cross Airfield 33.3 +0.3 41.8 25th 16.2 +0.5 6.3 1st 4.0 15.5 low 26%
North East (district 13)
Carnegie 36.1 -1.6 40.9 31st 20.2 -2.1 15.3 16th 82.3 25.2 v high 327%
Giles Meteorological Office 33.9 -2.0 41.9 4th 21.1 -0.9 15.7 23rd 127.0 47.9 v high 265%
Telfer Aero 37.8 -2.6 44.0 17th 25.7 +0.1 19.3 10th
Warburton Airfield 34.0 -2.8 41.7 4th 21.1 -0.4 16.4 1st 137.2 33.1 v high 415%
Wiluna Aero 36.9   41.9 26th 22.3   16.9 1st 10.8
Offshore Islands (district 200)
Adele Island 30.9   32.7 5th 26.0   22.5 22nd
Rowley Shoals 30.2   32.2 25th 27.4   25.2 10th
Varanus Island 31.7 +0.5 34.2 3rd 25.8 +0.9 21.2 14th 72.6 5.8 highest 1252%

Notes

The Monthly 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 8 am on Monday 4 January 2021. 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

Creative Commons By Attribution logo Unless otherwise noted, all maps, graphs and diagrams in this page are licensed under the Creative Commons Attribution 4.0 International Licence

Climate