Western Australia in December 2017: Above average temperatures

Rainfall was above average for Western Australia as a whole, whilst both mean maximum and minimum temperatures for the State were above average.

Above average rainfall in the west Kimberley and near the west coast

  • Monthly rainfall was 53% above average for WA, wettest December for two years
  • Above average rainfall was reported in the west Kimberley, parts of inland WA, the Eucla, and near the west coast, whilst below average rainfall was recorded in parts of the Goldfields and Pilbara
  • A cold front and associated deep low pressure system brought unseasonal rainfall to the South West Land Division (SWLD) between the 17th and 19th; Bickley in the Perth hills broke its December daily record on the 18th with 36.4 mm
  • Tropical cyclone Hilda produced daily rainfall in the 100 mm to 300 mm range in the west Kimberley from the 27th to 29th; a number of December daily rainfall records were broken including 291.5 mm on the 27th at Cygnet Bay, the country's highest daily fall of the month
  • A number of sites in the west Kimberley, Lower West and South West either recorded their wettest December on record or wettest for at least 20 years, whilst Carnegie in the Southern Interior equalled its December rainfall record after several episodes of thunderstorm activity

Above average daytime and overnight temperatures for WA

  • The mean maximum temperature for WA was 0.62 °C above average, but only the highest for two years
  • Above average mean maxima were reported in the Eucla, parts of the SWLD, Gascoyne, and west Kimberley, whilst below average daytime temperatures were confined to the Interior and coastal Pilbara
  • The mean minimum temperature for WA was 0.64 °C above average, the highest for five years
  • Above average mean minimum temperatures were recorded across much of WA, with only small parts of the Kimberley recording below average overnight temperatures
  • Badgingarra Research Station in the Lower West recorded its lowest maximum temperature in December on the 18th as a southerly burst brought unusually mild conditions to the SWLD
  • Curtin Aerodrome in the Kimberley recorded its lowest maximum temperature in December on the 27th as tropical cyclone Hilda passed to the west and brought persistent cloud and heavy rain
  • Northerly winds and cloudy skies brought 8 °C to 12 °C above average daily minima along the south coast with a December minimum temperature record at Jacup on the 11th
  • Troughton Island off the north Kimberley coast recorded its highest December minimum temperature on record on the 12th as moderate west to northwesterly winds kept the temperature above 30 °C
  • Newman Aerodrome equalled its highest December mean minimum temperature on record

Tropical cyclone Hilda

  • Tropical cyclone Hilda was the first tropical cyclone to affect the Australian mainland in the 2017-18 season. A tropical low tracked south-southwest parallel to the northwest Kimberley coast and developed into tropical cyclone Hilda in the late afternoon on the 27th near Broome, reaching category 2 intensity prior to making landfall north of Bidyadanga in the evening. The system moved south and weakened to a tropical low on the 28th. Hilda affected mostly the west Kimberley coast between Broome and Bidyadanga with some structural and vegetation damage, and brought significant rainfall to the west Kimberley.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in December 2017
Hottest day 46.7 °C at Onslow Airport on the 24th
Warmest days on average 42.3 °C at Marble Bar
Coolest days on average 21.5 °C at Albany
Coldest day 15.4 °C at Mount Barker on the 6th
Coldest night 2.5 °C at Jarrahwood on the 1st
Coolest nights on average 10.6 °C at Jarrahwood
Warmest nights on average 27.9 °C at Troughton Island
27.5 °C at Broome Airport
Warmest night 31.4 °C at Warburton Airfield on the 23rd
Warmest on average overall 34.3 °C at Marble Bar
Coolest on average overall 17.8 °C at Windy Harbour
Wettest overall 621.7 mm at Cygnet Bay
Wettest day 291.5 mm at Cygnet Bay on the 27th
Strongest wind gust 106 km/h at Cape Leeuwin on the 17th

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
Derby Aero 150.4 on the 28th 147.4 on the 22nd in 2016 57
Cygnet Bay 291.5 on the 27th 209.4 on the 16th in 1993 54
Bickley 36.4 on the 18th 35.6 on the 31st in 1983 47
Kilto Station 201.0 on the 28th 116.8 on the 24th in 2008 36
Willare Bridge 116.4 on the 28th 84.2 on the 20th in 1998 20



Record highest December total rainfall
New record
(mm)
Old
record
Years of
record
Average for
December
Carnegie 98.0 = 98.0 in 1995 63 24.8
Cygnet Bay 621.7 416.4 in 1993 52 89.4
Bickley 64.4 41.0 in 2011 47 14.9
Rosa Brook 77.7 74.2 in 1944 45 22.5
Country Downs 446.6 398.3 in 1970 43 129.5
Kimbolton 490.8 424.0 in 2016 33 148.3

Highest December total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Average for
December
Mount Helena 52.0 61.0 in 1991 13.4
Boyup Brook 67.8 91.2 in 1995 15.1
Telfer Aero 146.8 209.3 in 1995 48.5
Cowaramup 50.6 56.4 in 1996 19.0
Margaret River 63.4 70.4 in 1996 19.8

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




Lowest December total rainfall for at least 20 years
Observed
(mm)
Most recent
lower
Average for
December
Argyle Aerodrome 59.0 35.5 in 1992* 139.5

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




Record lowest December daily maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Badgingarra Research Stn 20.3 on the 18th 21.0 on the 11th in 2005 49 32.0
Curtin Aero 25.4 on the 27th 25.7 on the 18th in 2009 27 38.3



Record highest December daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Troughton Island 30.3 on the 12th 30.1 on the 10th in 2016 39 27.3
Jacup 21.8 on the 11th 21.7 on the 27th in 2007 25 11.5



Record highest December mean daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Newman Aero 25.1 = 25.1 in 2009 21 23.9



Record lowest December mean temperature
New record
(°C)
Old
record
Years of
record
Average for
December
Warmun 30.2 30.3 in 2000 54 31.8



Summary statistics for December 2017
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
December
2017
Diff
from
average
Highest for
December
2017
Mean for
December
2017
Diff
from
average
Lowest for
December
2017
Total for
December
2017
Average
for
December
Rank of
December
2017
Fraction of
December
average
North Kimberley (district 01)
Doongan 35.0 +0.6 39.0 12th 22.8 -0.3 20.0 30th 155.6 230.7 low 67%
Kalumburu 35.3 +0.1 39.6 11th 24.4 -0.5 22.0 23rd 278.6 246.3 average 113%
Mount Elizabeth 34.5 +0.4 38.8 18th 22.9 +0.5 20.6 30th 93.3 170.7 low 55%
Troughton Island 33.8 +0.8 35.6 13th 27.9 +0.6 23.7 15th 186.4 125.2 high 149%
Truscott 34.3 +0.2 36.9 12th 26.0 0.0 22.3 15th 288.0 205.3 high 140%
Wyndham Aero 37.8 0.0 42.0 13th 26.4 -0.3 21.0 15th 154.0 151.3 average 102%
East Kimberley (district 02)
Argyle Aerodrome 38.2 +1.0 42.9 12th 26.5 +0.6 21.5 15th 59.0 139.5 v low 42%
Halls Creek Airport 37.5   43.1 13th 24.7   21.4 22nd 114.8
Kununurra Aero 37.4 +0.3 42.2 13th 25.6 +0.2 22.8 15th 119.8 141.2 average 85%
Warmun 36.9 -1.4 45.1 9th     20.3 15th 117.1 120.1 average 98%
West Kimberley (district 03)
Bidyadanga 34.7 -0.3 38.0 2nd 27.0 +1.2 22.0 28th 285.0 59.7 v high 477%
Broome Airport 34.5 +0.6 38.3 2nd 27.5 +1.0 23.6 25th 139.2 63.3 high 220%
Curtin Aero 38.8 +0.5 42.1 2nd 25.6 +0.5 21.6 10th 140.6 153.6 average 92%
Cygnet Bay 34.8 0.0 38.0 12th 25.8 +0.3 23.2 23rd 621.7 89.4 highest 695%
Derby Aero 37.7 +0.5 41.7 12th 26.4 +0.1 21.5 25th 227.2 78.8 v high 288%
Fitzroy Crossing Aero 39.0 0.0 43.9 13th 25.5 -0.2 22.3 6th 145.4 142.4 average 102%
De Grey (district 04)
Bedout Island 33.6   35.8 28th 27.3   25.9 18th
Karratha Aero 35.4 -0.4 41.6 26th 26.1 +0.5 22.3 19th 7.2 13.9 average 52%
Legendre Island 32.3   36.0 26th 25.8   23.8 18th
Mandora 36.9 +0.2 42.9 25th 25.3 +0.8 21.2 21st 12.6 33.9 average 37%
Marble Bar 42.3 +0.6 45.0 15th 26.3 +0.2 21.6 8th 28.2 32.4 average 87%
Pardoo Station     43.5 25th 25.4 +0.6 21.5 19th 1.5 24.0 average 6%
Port Hedland Airport 36.9 +0.3 40.7 28th 25.5 +1.4 22.7 20th 33.6 18.9 high 178%
Roebourne Aero 39.2 -0.1 43.6 26th 25.4 +0.6 21.8 20th 8.4 14.2 average 59%
Fortescue (district 05)
Barrow Island Airport 33.1 +0.9 37.6 25th     22.0 11th 5.2 5.6 high 93%
Learmonth Airport 37.1 +0.2 45.1 24th 21.9 +1.1 16.8 19th 3.0 6.1 high 49%
Mardie 36.7 -0.8 43.0 24th 24.1 +1.1 19.5 1st 0 8.9 lowest 0%
Onslow Airport 35.9 0.0 46.7 24th 24.0 +1.7 20.5 18th 3.2 3.4 high 94%
Thevenard Island 32.9 +0.9 38.7 24th 24.5 +0.8 21.4 11th 7.4 7.6 high 97%
Wittenoom 40.1 +0.4 44.5 15th 26.5 +1.0 23.1 7th 35.4 49.1 average 72%
West Gascoyne (district 06)
Carnarvon Airport 31.3 +1.9 40.5 8th 21.7 +1.0 18.4 1st 10.6 5.5 v high 193%
Denham 29.9 +0.7 41.0 8th 21.5 +1.0 18.5 20th 1.4 2.3 high 61%
Emu Creek Station 40.1 +0.2 46.2 24th 22.7 +0.3 17.9 18th 0 13.1 lowest 0%
Murchison 36.7 -0.7 43.0 22nd 21.3 +1.1 15.0 18th 29.4 14.0 high 210%
Shark Bay Airport 33.6 +1.4 43.6 2nd 20.3 +0.7 16.3 20th 1.2 9.4 high 13%
East Gascoyne (district 07)
Newman Aero 39.1 0.0 43.4 23rd 25.1 +1.2 19.0 19th 2.0 36.2 low 6%
Paraburdoo Aero 40.8 +0.4 45.1 23rd 26.0 +1.5 18.2 19th 2.6 26.9 low 10%
Murchison (district 07A)
Meekatharra Airport 37.0 +0.5 43.0 22nd 23.6 +1.5 15.5 18th 7.8 14.7 average 53%
Mount Magnet Aero 36.4 +0.7 43.4 22nd 21.7 +0.6 14.4 18th
Paynes Find 36.0 +1.0 42.4 22nd 19.9 +1.5 13.1 19th 5.4 12.6 average 43%
North Coast (district 08)
Dalwallinu 33.3 +0.2 39.2 31st 16.6 +0.9 11.4 18th 0.6 12.9 low 5%
Geraldton Airport 31.4   43.4 8th 17.2   10.2 1st 9.6
Kalbarri 31.7 +0.5 42.5 8th 19.1 +1.6 14.4 1st 7.2 3.8 high 189%
Mullewa 34.9 +0.4 41.6 21st 19.0 +2.0 14.2 18th 24.9 8.5 v high 293%
North Island 26.8 +0.2 28.9 10th 20.5 +0.5 17.1 18th 3.6 3.5 high 103%
Wongan Hills     39.2 21st 16.1 +0.3 10.7 18th 7.2 10.0 average 72%
Central Coast (district 09)
Badgingarra Research Stn 32.1 +0.1 39.0 21st 16.1 +1.1 11.9 18th 17.8 9.3 high 191%
Bickley 28.5 +0.5 35.3 10th 13.9 +0.3 9.1 1st 64.4 14.9 highest 432%
Garden Island HSF 25.4 0.0 35.1 3rd 17.5 +0.3 13.6 1st 24.0 11.5 high 209%
Gingin Aero 30.9 +0.3 37.9 11th 14.9 +0.6 10.9 18th 38.6 11.0 v high 351%
Jandakot Aero 29.7 +0.7 37.0 10th 15.8 +1.2 11.2 19th 27.2 11.0 high 247%
Jurien Bay 29.3 +1.1 38.8 8th 16.2 +0.6 11.2 20th 16.0 6.7 high 239%
Lancelin 27.3 0.0 36.6 8th 16.0 -0.2 11.5 18th 44.8 8.6 v high 521%
Millendon (Swan Valley) 31.3   38.2 10th 15.7   11.2 18th 35.6
Pearce RAAF 32.0 +1.7 39.4 10th 15.9 +1.4 11.4 2nd 36.6 11.3 high 324%
Perth Airport 30.6 +1.6 38.4 10th 16.4 +1.5 11.9 2nd 28.6 11.4 v high 251%
Perth Metro 29.7 +0.6 37.7 10th 16.7 +0.4 12.4 18th 40.6 13.1 v high 310%
Rottnest Island 25.1 +0.1 34.7 3rd 17.7 +0.1 11.4 18th 39.8 11.6 high 343%
Swanbourne 27.5 -0.4 35.9 3rd 17.3 +0.8 13.4 18th 13.6 11.9 average 114%
South Coast (district 09A)
Albany 21.5 -0.3 29.1 10th 14.8 +0.8 11.0 7th 51.0 30.4 high 168%
Albany Airport 23.8   33.5 10th 12.5   5.3 1st 55.6
Bridgetown 28.0 +0.6 37.8 10th 10.8 -0.2 2.8 1st 45.2 19.7 high 229%
Bunbury 28.1 +0.8 36.6 3rd 13.1 -0.4 6.3 1st 18.2 18.2 high 100%
Busselton Aero 28.0 +0.1 36.4 3rd 12.9 +0.6 6.5 1st 35.8 10.3 v high 348%
Cape Leeuwin 22.3 +0.5 24.5 25th 16.4 +0.6 11.1 1st 34.8 20.7 high 168%
Cape Naturaliste 25.5 +1.9 33.3 3rd 13.9 0.0 8.8 1st 23.8 13.6 high 175%
Collie East 29.2 +0.7 36.9 11th 11.0 -0.5 4.7 1st 35.4 22.9 high 155%
Donnybrook 29.2 +1.0 37.5 11th 13.2 +0.8 8.5 1st 51.2 16.5 v high 310%
Dwellingup 28.5 +1.2 35.9 11th 13.1 +0.5 8.0 1st 69.4 21.2 v high 327%
Esperance 25.3 +0.7 37.1 10th 14.6 +0.2 8.7 2nd 15.6 19.8 average 79%
Esperance Aero 27.2 +1.4 38.8 10th 13.2 -0.2 8.6 1st 24.0 21.6 average 111%
Hopetoun North 24.0 0.0 38.9 10th 14.2 +0.5 7.5 8th 17.2 25.8 average 67%
Jarrahwood 28.4 +1.3 37.0 10th 10.6 -0.5 2.5 1st 46.0 17.3 v high 266%
Mandurah 27.2 +0.2 35.1 3rd 17.5 +0.4 13.3 1st 33.8 17.4 high 194%
Manjimup 26.4 +1.5 37.4 10th 11.8 +0.1 6.3 1st 46.8 25.5 high 184%
North Walpole 22.9 +0.5 31.3 9th 13.1 +0.3 8.9 8th 71.4 44.8 high 159%
Rocky Gully 25.9 +0.5 38.0 10th 11.3 +0.3 3.1 1st 30.0 30.7 average 98%
Shannon 24.7 +0.4 35.1 9th 11.4 +0.2 4.4 1st 53.4 30.6 high 175%
Windy Harbour 22.0 +0.1 24.3 9th 13.6 +0.5 5.3 18th 32.3 28.2 average 115%
Witchcliffe 25.0 +0.3 34.0 10th 13.1 +0.8 5.2 1st 68.2 17.8 v high 383%
North Central (district 10)
Bencubbin 32.1 -0.3 38.8 26th 16.9 +0.9 11.1 1st 4.9 13.2 average 37%
Cunderdin Airfield 33.3 +0.5 39.6 25th 15.2 +0.4 10.5 1st 23.4 9.1 high 257%
Merredin 32.7 +0.7 38.7 25th 16.3 +0.5 10.7 1st 3.0 14.0 average 21%
Northam 32.5 +0.4 39.4 11th 14.4 -0.9 9.4 1st 15.0 9.3 high 161%
York       14.2 +0.3 7.0 1st 17.0 13.3 average 128%
South Central (district 10A)
Beverley 32.5 +0.3 39.6 11th 14.5 +0.2 8.4 1st 15.0 10.6 high 142%
Brookton 31.4 +0.4 38.4 11th 14.3 +0.8 9.0 1st 14.8 10.6 high 140%
Corrigin 31.4 +0.9 38.4 26th 14.3 +0.3 8.4 1st
Hyden 32.6 +0.8 40.0 11th 13.5 -0.3 6.0 1st 5.6 14.7 average 38%
Jacup 27.3 +1.1 38.8 10th 11.0 -0.5 4.4 1st 26.2 30.1 average 87%
Katanning 29.0 +0.5 38.8 10th 11.6 -0.1 4.5 1st 0.8 25.8 low 3%
Lake Grace 29.7 +0.4 37.3 10th 13.5 0.0 6.6 1st 15.4 23.2 average 66%
Narembeen 32.7 +0.7 39.0 11th 15.0 +0.5 8.9 1st 6.4 12.9 average 50%
Narrogin 29.7 +0.8 36.8 11th 13.1 +0.7 7.5 1st 18.0 14.3 high 126%
Newdegate Research Station 30.2 +0.8 38.4 11th 11.9 +0.3 3.8 1st 10.4 15.7 average 66%
Ongerup 27.6 +0.4 38.8 10th 12.3 -0.1 5.8 1st 16.0 17.7 average 90%
Pingelly     38.0 11th 13.5 -0.4 7.5 1st 15.7 12.8 high 123%
Ravensthorpe 27.2 0.0 39.0 10th 13.0 +0.2 5.5 1st 8.6 24.1 low 36%
Wagin 30.3 +1.1 37.8 11th 12.8 -0.1 6.5 1st 15.4 13.4 high 115%
Wandering 30.3 0.0 37.7 10th 12.4 +0.4 5.5 1st 52.6 21.1 v high 249%
Eucla (district 11)
Eucla 27.9 +3.1 43.9 17th 15.4 +0.3 9.1 15th 40.8 18.8 high 217%
Eyre 28.8 +3.2 45.2 26th 13.8 -0.3 4.5 15th 52.5 21.2 high 248%
Forrest 31.6 +0.1 45.0 26th 15.4 +0.5 8.6 2nd 17.4 25.2 average 69%
Red Rocks Point 26.0 +1.4 41.1 17th 16.0 -0.5 11.1 21st 38.2 21.0 high 182%
South East (district 12)
Bulga Downs 36.2 +0.1 43.7 22nd 20.6 +0.5 13.7 18th 1.0 13.2 low 8%
Kalgoorlie-Boulder Airport 32.5 +0.5 42.6 22nd 17.3 +0.7 12.0 20th 3.0 16.5 low 18%
Laverton Aero 34.4 +0.6 43.3 16th 19.8 +0.1 12.8 1st 22.0 28.0 average 79%
Leinster Aero 35.7 +0.3 43.3 16th 21.4 +0.2 15.4 18th 4.2 26.4 low 16%
Leonora Aero 35.3 +0.1 44.4 16th 21.1 +0.3 14.5 1st 1.4 14.3 v low 10%
Munglinup West 27.6 +0.2 39.2 10th 12.5 -0.1 6.3 1st 10.2 29.7 low 34%
Norseman Aero 31.9 +0.9 43.3 22nd 13.9 0.0 5.1 1st 1.0 21.1 v low 5%
Salmon Gums Res.Stn. 29.6 +0.6 37.5 11th 12.1 -0.1 3.7 1st 20.0 20.0 average 100%
Southern Cross Airfield 32.8 +0.1 42.0 22nd 15.9 +0.4 10.0 1st 0.2 14.9 v low 1%
North East (district 13)
Carnegie 35.9 -1.6 42.8 23rd 21.8 -0.4 17.0 1st 98.0 24.8 highest 395%
Giles Meteorological Office 36.8 +1.0 42.9 24th 22.0 +0.1 16.2 3rd 33.6 46.7 average 72%
Telfer Aero 40.3 0.0 44.8 24th 26.5 +1.0 22.0 29th 146.8 48.5 v high 303%
Warburton Airfield 36.3 -0.4 43.6 23rd 22.3 +0.9 14.5 1st 0 31.7 lowest 0%
Wiluna 36.5 -0.4 43.5 22nd 22.2 +1.1 16.0 18th 22.0 22.3 average 99%
Wiluna Aero 37.3   43.2 16th 22.8   16.4 18th 25.0
Offshore Islands (district 200)
Browse Island 31.6   33.4 22nd     23.1 26th
Varanus Island 31.1 -0.1 34.4 24th 25.3 +0.4 22.6 18th 1.2 2.8 high 43%
Note: Observations for “Perth Metro” are taken from the current site at Mount Lawley (Bureau number 009225).
Comparisons are made against combined data from the current site (which opened in early 1993) and the previous site at Perth Regional Office (009034), which ran from 1876 to early 1992.
From 2017 on, information about Cocos and Christmas Islands can be found in the climate summary for the Remote Islands and Antarctica

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 9 am on Tuesday 9 January 2018. 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
Enquiries