Western Australia in 2010: A very dry year in southwest Western Australia

  • Rainfall: Near average for WA as a whole; driest year on record for southwest WA.
  • Maximum temperature: Ninth warmest on record for WA; second warmest for southwest WA.
  • Minimum temperature: Third warmest for WA; near average for southwest WA.

Rainfall

Annual: Annual rainfall in 2010 in WA was above average to very much above average in parts of the Kimberley, northern and eastern Interior and eastern Eucla. Eucla in the southeast of the state recorded its wettest year in 121 years of record. The rainfall was associated with tropical weather systems, with persistent cloud bands that brought significant rain through the dry season to northern and eastern WA. Also, after a very dry year, parts of the Gascoyne region received record rainfall in December to register very much above average rainfall for 2010.

In marked contrast, the Southwest Land Division (SWLD) and adjacent parts of neighbouring districts recorded below average rainfall. Averaged across the SWLD it was the driest year since comparable records commenced in 1900, whilst the Lower Southwest (southwest of a line from Jurien Bay to Bremer Bay) also experienced its driest year on record by a significant margin, the driest southern wet season (April to October), driest winter (June to August), and driest spring (September to November). Many sites in the Southwest, Lower West, Great Southern and Central Wheat Belt observed approximately half, or less, of the normal average annual rainfall, and the driest year on record.

The statewide annual mean total was 334 mm, which is close to the average of 341 mm.

January: Rainfall during January 2010 over WA was close to the long-term mean. A tropical low that moved south near the WA/NT border at the beginning of the month brought above average rainfall to eastern parts of the state, whilst Tropical Cyclone Magda toward the end of the month brought heavy falls to the west Kimberley. Persistent strong high pressure systems to the south of the state prevented any meaningful rainfall for large parts of western and inland WA in January. In particular, there was a weaker than normal level of thunderstorm activity near the SWLD west coast and many stations in this region recorded no rainfall for the month.

February: Rainfall for February 2010 was below average with an unusually quiet monsoon season and no tropical cyclones in the WA region. This lack of monsoonal activity also had an effect on the remainder of the state, with few opportunities for tropical moisture to venture into western parts resulting in below average rainfall conditions in west coast districts. Severe thunderstorms causing damage and heavy rainfall in the south of the SWLD on the 9th led to small pockets of above average rainfall.

Autumn: Below average rainfall continued in the SWLD, as well as in the Pilbara and large parts of the Gascoyne in autumn. The first significant rainfall for the year for many locations in the southern Gascoyne and western SWLD came on 21 and 22 March 2010 as low level convergence into a surface trough combined with a mid-level trough off the WA west coast to generate showers and storms in the region. Severe thunderstorms occurred in Perth and southwest WA on the afternoon of 22 March and caused significant damage, being considered as one of the worst storms in Perth's history. For more details of the severe thunderstorms in Perth, see notable events below.

Winter: Averaged over the state as a whole, rainfall during winter 2010 was near average; however, for the Lower Southwest, very dry conditions that had been present for much of the year continued and the region posted its driest winter since comparable records commenced in 1900 as a result of the third driest June on record, a below average July, and the sixth driest August on record. The SWLD recorded its 2nd driest winter on record, only eclipsed by the drier winter of 2006. In contrast, above to very much above average winter rainfall was recorded over most of the Kimberley and adjacent Pilbara and Interior, the result of above average July and August rainfall. Cloudbands in mid-June and early July produced unusually heavy falls in the Pilbara and Kimberley with several daily winter rainfall records broken.

Spring: WA observed its 5th highest spring rainfall as a result of above average rainfall over most of WA, apart from the SWLD. Above average September and October rainfall with significant cloudbands in September, as well as thunderstorm activity through the spring months, contributed to the very much above average spring rainfall to much of WA. In stark contrast, the SWLD continued to experience a very dry year with very much below average rainfall across most of the region. The Lower Southwest recorded its driest spring on record, and the SWLD its 5th driest spring on record.

December: Most of western WA recorded above average rainfall during December as a result of an early monsoon onset, and the passage of a tropical low near the WA west coast during the middle of the month. The low brought falls of over 300 mm to parts of the west Gascoyne region, resulting in significant flooding in the Gascoyne River and inundation of parts of Carnarvon.

Maximum temperature

Annual: Maximum temperatures in WA during 2010 were above average to very much above average for the western half of the state, with areas of hottest on record in western parts of the SWLD, including Perth, as well as in the west Kimberley. In contrast, eastern parts of the Kimberley and Interior were below average in terms of daytime maximum temperatures. Averaged across the state as a whole, the annual mean maximum temperature was 0.70 °C above the 1961/90 average, and the 9th warmest year since records commenced in 1910. The Lower Southwest observed its 2nd warmest year on record, 1.23 °C above the 1961/90 mean. The west Pilbara experienced a very hot start to the year with Onslow recording a maximum temperature of 49.2 °C on 1 January 2010, the highest temperature recorded in WA in 2010 and an equal record highest temperature at Onslow.

January: Very hot daytime temperatures were observed over much of the state during January 2010. Several daily maximum temperature records for January were broken or equalled in the Pilbara on the first two days of the month, with maxima near to or exceeding 49 °C. In the south, a near stationary trough off the west coast on 6 January combined with a high in the Bight to direct hot northeasterly winds over the SWLD with several sites in eastern parts of the SWLD having their hottest day on record. Hopetoun North, in the Southeast Coastal district, recorded a maximum temperature of 48.0 °C. The event was marked by "catastrophic" high fire danger ratings in the region and a notable number of heat related bird deaths.

February: Above average to very much above average temperatures continued in much of WA during February 2010, with the daytime maximum for the state ranking as the 4th hottest for February. Inland parts of WA generally saw the greatest departures from normal, with little cloud or rainfall to moderate temperatures during the month.

Autumn: Above average to very much above average mean maximum temperatures were recorded in almost all of WA in autumn 2010, and the season ranked as the 6th hottest on record.

Winter: Winter mean maximum temperatures were near average over much of central and southern WA, however, above average to very much above average mean maximum temperatures occurred in the north and west Kimberley, the Pilbara, north and west Gascoyne, and western parts of the SWLD, with Roebourne and Onslow in the Pilbara experiencing their warmest winter on record.

Spring: Spring mean maximum temperatures were above average to very much above average over western WA, with the Lower Southwest observing its warmest spring on record. In contrast, mean maximum temperatures for spring 2010 were below average to very much below average over eastern and central WA, with Giles and Balgo Hills in the Interior experiencing their coolest spring maximum temperatures on record.

December: Mean maximum temperatures were near average across the WA as a whole, however the Lower Southwest experienced many hot and humid days in the second half of the month.

Minimum temperature

Annual: Minimum temperatures in 2010 in WA were above average to very much above average in most of the state and sites in the west Kimberley, Pilbara and north Gascoyne observed their highest annual mean minimum temperatures on record. In contrast, most of the SWLD, as well as parts of the eastern Interior and southeast Kimberley recorded near average overnight minima in 2010. Averaged across the state as a whole, the annual mean minimum temperature was 0.74 °C, well above the 1961/90 average and the 3rd warmest since comparable records commenced in 1910.

January: Above average overnight temperatures were observed over most of the state during January 2010, particularly in central and southern parts. Balladonia, in the Eucla district, recorded its highest overnight temperature in 46 years of record with 27.8 °C on the 10th.

February: Above to very much above average minimum temperatures continued for much of WA in February 2010. Inland parts of WA generally saw the greatest departures from normal, with pockets of record high mean minimum temperatures.

Autumn: Mean minimum temperatures were above to very much above average through much of WA away from the west coast, and the season ranked as 4th warmest on record averaged across WA as a whole.

Winter: When averaged over the whole state, winter 2010 was above average, with northern and central parts reporting above average mean minima, however most of the SWLD, southern Gascoyne and southern Goldfields experienced abnormally cold minima as a result of low cloudiness and low rainfall. Several sites in the SWLD and Goldfields registered their lowest winter temperature on record in late June or early July. Eyre recorded a minimum temperature of -6.8 °C on 11 August 2010, the second lowest temperature recorded in WA (the record is -7.2 °C recorded at Eyre on 17 August 2008). In contrast, Mardie and Onslow Airport on the west Pilbara coast recorded their warmest winter on record in terms of mean overnight temperatures.

Spring: Above average mean minima were recorded in much of the west Kimberley, Pilbara, Gascoyne, and northern SWLD in spring, whilst below average minima were recorded near the WA south coast and in the northeast Interior and southeast Kimberley. Averaged across the state, a near average mean minimum temperature was recorded in spring.

December: Above average mean minimum temperatures were reported across much of WA in December, whilst only in the Kimberley were large areas of below average mean minima reported. As a result the WA mean minimum for December was above average.

Notable events

  • Summer 2009/10 was particularly hot for WA with the summer mean temperature (average of maximum and minimum) being the highest on record. All months during the summer were abnormally hot with the third hottest December, second hottest January, and third hottest February recorded.
  • The 2009/10 Tropical Cyclone Season in the north of WA was notable for a lack of tropical cyclones. No tropical cyclones were recorded in the WA region in February or March. However, two coastal crossings did occur during the tropical cyclone season, with TC Laurence (late December 2009) and TC Magda (January 2010) crossing the Kimberley coast as severe tropical cyclones. The west Pilbara and Gascoyne region received no tropical cyclone activity during the season.
  • Severe storms affected southern WA on 21 and 22 March. Storms that swept through the Perth metropolitan area and southwest WA on the afternoon of 22 March, were considered to be some of the worst in Perth's history with over $1 billion in damage caused mainly by large hail (up to 6 cm) and flash flooding. The storms brought the first significant rainfall to Perth after a long dry spell that commenced on 20 November 2009 and included Perth's driest summer since records commenced in 1876.
  • The Kimberley and northern Interior recorded an exceptionally wet "dry season" (May to October), with several sites reporting their highest seasonal rainfall on record.
  • An extraordinarily dry year occurred in southwest WA with a very low number of cold frontal systems moving through the region during autumn, winter and spring. The Lower Southwest recorded a below average autumn, the driest winter and the driest spring since comparable records commenced in 1900, and this culminated in the driest year on record for the region by some margin.
  • A significant tropical depression brought over 300 mm to western parts of the Gascoyne district in mid-December, and caused major flooding in the Gascoyne River and in Carnarvon. Many daily and monthly rainfall records were broken as a result. Carnarvon registered its wettest month since records commenced in the town in 1883, with a December total of 255.0 mm observed at Carnarvon Airport, and a daily total of 207.8 mm in the 24 hours to 9am on 17 December.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in 2010
Hottest day 49.2 °C at Onslow on 1 Jan
Warmest days on average 36.2 °C at Fitzroy Crossing Aero
Coolest days on average 19.8 °C at Albany
Coldest day 9.0 °C at Mount Barker on 18 Aug
Coldest night -6.8 °C at Eyre on 11 Aug
Coolest nights on average 7.9 °C at Jarrahwood
Warmest nights on average 26.5 °C at Troughton Island
23.9 °C at Truscott (mainland)
Warmest night 34.6 °C at Paraburdoo Aero on 2 Jan
Wettest overall 1620.9 mm at Theda (Kimberley)
Driest overall 72.8 mm at Mardie
Wettest day 215.6 mm at Cape Leveque on 19 May
Highest wind gust 128 km/h at Cunderdin Airfield on 22 Mar

Record highest annual daily rainfall
Highest daily rainfall
in 2010 (mm)
Previous annual
highest
Years of
record
Twin Peaks 163.0 on 18 Dec 150.0 on 22 Feb 1975 102
Marron 166.4 on 17 Dec 132.4 on 9 Mar 2000 99
Yaringa Station 179.0 on 17 Dec 175.0 on 9 Mar 2000 85
Carnarvon Airport 207.8 on 17 Dec 102.6 on 13 Jul 1998 66
Alexandra Bridge 82.0 on 27 May 78.0 on 27 Jan 1974 40



Record highest total annual rainfall
Total rainfall
for 2010 (mm)
Previous annual
highest
Years of
record
Annual
average
Eucla 450.3 439.8 in 2006 121 271.3



Record lowest total annual rainfall
Total rainfall
for 2010 (mm)
Previous annual
lowest
Years of
record
Annual
average
Bannister 318.2 341.1 in 1969 126 646.4
Bridgetown Comparison 399.9 510.1 in 1940 122 823.8
Greenbushes 467.9 603.6 in 2006 116 932.8
Broomehill 233.5 253.2 in 1954 115 448.3
Marradong 320.5 403.3 in 1914 112 723.9
Donnybrook 511.3 618.7 in 2006 108 975.9
Mundaring 599.6 653.4 in 1914 107 1072.4
Nannup 547.2 596.1 in 2006 103 947.3
Corrigin 166.5 214.4 in 1914 101 372.9
Lake Grace Comparison 155.6 187.0 in 2009 98 350.2
Quairading 162.7 185.5 in 1914 98 367.1
Bencubbin 118.4 123.3 in 1914 96 315.2
Tambellup 236.3 261.4 in 1940 96 448.8
Belka 143.6 163.1 in 1969 94 330.0
Manjimup 549.0 650.3 in 1940 91 1006.6
Doodlakine 129.0 144.6 in 1914 88 310.5
Kulin 190.4 210.5 in 1972 86 360.4
Cherry Tree 264.6 277.6 in 1940 82 458.6
Holt Rock 147.8 164.0 in 2002 82 328.3
Boscabel 285.0 288.9 in 1940 81 519.5
Bungulla 151.5 158.7 in 1994 79 310.2
Hyden 142.1 157.8 in 1972 79 338.6
Northcliffe 787.6 828.5 in 1969 78 1332.7
Graham Rock 140.2 174.7 in 1972 74 340.7
Dwellingup 589.7 751.8 in 1940 72 1245.2
Wongan Hills Res.Station 195.8 214.3 in 1972 72 354.6
Roelands 476.0 585.6 in 2001 68 890.5
Waroona 485.2 560.2 in 1940 68 995.6
Woodanilling 261.1 298.5 in 1944 68 461.7
Beacon 129.5 162.1 in 1940 67 314.6
Pemberton 669.1 802.0 in 1969 67 1191.4
Gabbin 126.1 165.5 in 1969 65 334.5
Karlgarin 91.9 169.1 in 1980 64 328.1
Goodlands 138.2 139.4 in 1976 57 312.3
Amrista Park 143.9 208.7 in 1972 53 354.8
Gordon River 309.3 355.8 in 1972 50 529.1
Swanara 153.2 177.8 in 1972 45 340.0
Gidgegannup 489.4 573.7 in 1969 43 890.5
Lancelin 342.0 428.0 in 2006 43 603.2
Pearce RAAF 347.2 458.8 in 1969 42 658.5
Gosnells City 499.6 553.1 in 2006 41 830.5
Karnet 596.3 655.8 in 1994 41 1170.8
Bickley 572.8 674.9 in 1969 39 1076.8
Culford 386.4 465.6 in 2004 34 657.8
Ferguson Valley 527.2 629.4 in 2006 34 898.2
Jarrahwood 526.8 661.9 in 2006 34 929.5
Jandakot Aero 495.8 509.8 in 2006 33 829.0
Chillinup 266.2 302.3 in 2009 31 414.4




Record highest annual temperature
Highest temperature
in 2010 (°C)
Previous annual
highest
Years of
record
Annual
average
Esperance 46.9 on 6 Jan 46.7 on 1 Feb 1991 42 21.8
Learmonth Airport 48.9 on 2 Jan 48.2 on 21 Jan 2003 36 31.8



Record lowest annual daily maximum temperature
Lowest daily maximum
temperature
in 2010 (°C)
Previous annual
lowest
Years of
record
Annual
average
Telfer Aero 13.1 on 5 Jul 13.6 on 9 Jul 1986 37 34.1



Record highest annual mean daily maximum temperature
Mean daily maximum
temperature
for 2010 (°C)
Previous annual
highest
Years of
record
Annual
average
Narrogin 23.7 23.6 in 1994 79 22.3
Dwellingup 23.6 23.1 in 1994 70 21.7
Manjimup 21.7 21.3 in 1994 69 20.3
Perth Airport 26.0 25.6 in 1999 65 24.4
Pemberton 21.6 21.5 in 1994 62 20.2
Corrigin 25.1 24.9 in 1994 58 23.7
Merredin 26.5 26.3 in 1972 44 24.9
Wongan Hills 26.9 26.8 in 1994 39 25.6
Pingelly 24.6 24.2 in 2009 37 23.2
Hyden 26.5 26.2 in 1994 33 25.0




Record highest annual daily minimum temperature
Highest daily minimum
temperature
in 2010 (°C)
Previous annual
highest
Years of
record
Annual
average
Balladonia 27.8 on 10 Jan 27.1 on 30 Dec 2009 46 9.8



Record lowest annual temperature
Lowest temperature
in 2010 (°C)
Previous annual
lowest
Years of
record
Annual
average
Geraldton Airport -0.4 on 4 Jul 0.5 on 26 Jun 1973 70 13.6
Norseman -4.6 on 27 Jun -3.1 on 21 Jul 1988 54 10.5
Narembeen -3.2 on 3 Jul -2.5 on 2 Jul 1982 44 10.6
Pingelly -2.5 on 3 Jul -1.6 on 22 Sep 2008 40 10.4



Record highest annual mean daily minimum temperature
Mean daily minimum
temperature
for 2010 (°C)
Previous annual
highest
Years of
record
Annual
average
Broome Airport 23.0 22.8 in 1959 70 21.2
Port Hedland Airport 21.3 21.0 in 1998 61 19.4
Onslow Airport 20.1 20.0 in 2004 41 18.9
Emu Creek Station 19.4 19.0 in 1998 36 18.2
Gascoyne Junction 18.0 17.7 in 1996 31 16.8





Summary statistics for 2010
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean
for
2010
Diff
from
average
Highest
for
2010
Mean
for
2010
Diff
from
average
Lowest
for
2010
Total
for
2010
Average
annual
total
Rank
of
2010
Fraction
of annual
average
North Kimberley (district 01)
Kalumburu 34.0 -0.3 38.8 6 Apr 21.7 +1.4 9.9 13 Aug 1322.8 1163.5 high 114%
Troughton Island 31.7 +0.7 35.1 26 Nov 26.5 +1.2 21.3 2 Aug   784.7    
Truscott 32.7   38.0 21 Nov 23.9   15.8 13 Aug  
Wyndham 35.4 -0.2 41.8 7 Dec 23.8 +0.6 14.0 13 Aug 1017.2 814.1 high 125%
Wyndham Aero 35.7   42.6 7 Dec 23.5   12.0 5 Jun 893.6 816.5 high 109%
East Kimberley (district 02)
Argyle Aerodrome 34.3 -0.4 42.1 24 Nov 22.8 +0.6 13.1 7 Aug 886.6 767.9 high 115%
Halls Creek Airport 33.0 -0.6 42.2 1 Jan 20.7 +0.7 10.1 2 Jul 750.4 559.4 high 134%
Kununurra Aero 34.3 -0.6 42.4 22 Nov 21.9 +0.6 11.0 14 Aug 994.4 812.5 high 122%
West Kimberley (district 03)
Bidyadanga 34.2 +0.9 43.0 25 Mar     11.0 7 Aug 375.0 508.3 low 74%
Broome Airport 33.0 +0.8 40.7 9 Mar 23.0 +1.8 10.9 24 Jun 543.0 602.9 average 90%
Curtin Aero 35.7 +0.2 42.7 23 Nov 22.1 +1.1 12.4 16 Aug   816.5    
Derby Aero 34.8 +0.3 42.2 17 Nov 22.7 +1.2 12.6 21 Jun 817.8 681.3 high 120%
Fitzroy Crossing Aero 36.2 +0.2 44.9 24 Nov 21.1 +1.0 8.4 8 Aug 717.4 699.2 average 103%
West Roebuck 34.5   42.7 28 Sep 21.7   8.8 10 Aug 576.0 848.6 low 68%
De Grey (district 04)
Karratha Aero 32.9 +0.6 42.3 23 Mar 21.8 +1.1 10.6 11 Jul 95.4 282.4 v low 34%
Port Hedland Airport 34.0 +0.8 45.5 2 Jan 21.3 +1.9 9.2 11 Aug 125.6 309.8 low 41%
Roebourne 35.7 +1.7 47.2 16 Feb 21.2 +0.7 11.1 10 Jul 93.9 310.6 v low 30%
Roebourne Aero 35.2   46.4 16 Feb 20.8   8.6 11 Aug 145.6
Fortescue (district 05)
Barrow Island Airport 29.4 +0.3 40.0 2 Jan 22.5 +0.4 14.7 14 Jul 95.4 271.6 v low 35%
Learmonth Airport 32.7 +0.9 48.9 2 Jan 18.3 +0.6 6.1 25 Jul 266.2 250.6 average 106%
Mardie 34.1 +0.2 49.0 1 Jan 20.2 +1.5 8.4 11 Jul 72.8 271.1 v low 27%
Onslow 31.8 +0.5 49.2 1 Jan 20.4 +2.4 10.6 11 Jul 84.0 270.1 low 31%
Onslow Airport 32.7 +0.8 48.8 1 Jan 20.1 +1.2 10.3 11 Jul 80.4 318.2 v low 25%
Wittenoom 34.1 +1.2 46.5 1 Jan 20.8 +1.1 6.3 14 Jul 281.1 457.6 low 61%
West Gascoyne (district 06)
Carnarvon Airport 27.8 +0.6 44.2 11 Dec 17.4 +0.2 4.5 2 Jul 367.6 228.7 v high 159%
Denham     43.1 28 Feb 18.7 +1.2 8.6 28 Jun 231.0 223.8 average 103%
Emu Creek Station 34.8 +1.1 49.1 2 Jan 19.4 +1.2 7.5 10 Jul 198.0 299.1 average 66%
Gascoyne Junction 33.2 +1.1 47.6 27 Dec 18.0 +1.2 3.7 7 Jul
Shark Bay Airport 29.4   46.7 18 Jan 16.7   2.8 7 Jul 260.2 192.7 high 135%
East Gascoyne (district 07)
Newman Aero 32.7 +0.8 45.5 21 Feb 17.7 +1.7 0.9 2 Jul 216.4 319.3 low 68%
Paraburdoo Aero 34.6 +1.2 47.4 21 Feb 19.7 +1.8 4.5 25 Jul 135.0 316.6 v low 43%
Murchison (district 07A)
Meekatharra Airport 30.2 +1.3 44.9 31 Dec 16.7 +0.8 2.4 2 Jul 181.8 236.1 average 77%
Mount Magnet Aero 28.9 +0.5 45.4 31 Dec 15.8 +0.8 0.5 28 Jun 297.0 252.6 high 118%
North Coast (district 08)
Dalwallinu 26.9 +0.7 44.6 5 Jan 11.5 -0.1 -0.2 4 Jul 283.4 285.8 average 99%
Dalwallinu Comparison 27.0 +1.0 44.4 5 Jan 12.3 +0.1 -0.3 26 Jun 286.8 356.8 low 80%
Geraldton Airport 26.9 +1.0 45.8 18 Jan 13.2 -0.4 -0.4 4 Jul 301.6 443.6 v low 68%
Kalbarri 28.7 +1.1 45.4 18 Jan 14.7 +0.2 1.2 28 Jun 260.2 350.8 low 74%
Mullewa 29.1 +1.3 46.2 19 Jan 14.0 +0.9 1.9 2 Jul 338.3 333.9 average 101%
North Island 25.1   36.8 28 Feb 18.7   10.5 26 May 221.4
Wongan Hills 26.9 +1.3 44.7 19 Jan 11.8 -0.1 -0.8 25 Jun 223.3 387.7 v low 58%
Central Coast (district 09)
Bickley 23.4 +1.0 41.8 18 Jan 11.4 +0.3 2.4 25 Jun 572.8 1076.8 lowest 53%
Champion Lakes 25.1   41.5 17 Jan 13.6   2.7 4 Jul 446.2
Garden Island HSF 23.1   40.4 17 Jan 14.5   5.8 25 Jun 407.6
Gingin Aero 26.3 +1.0 44.3 18 Jan 10.2 -0.6 -3.7 5 Jul 421.8 630.0 v low 67%
Gosnells City 26.5 +1.2 43.8 17 Jan     0.5 26 Jun 499.6 830.5 lowest 60%
Jandakot Aero 25.7 +1.4 43.0 18 Jan 10.8 -0.5 -2.5 26 Jun 495.8 829.0 lowest 60%
Karnet 23.6 +1.1 40.2 18 Jan     -1.0 25 Jun 596.3 1170.8 lowest 51%
Lancelin 25.3 +1.3 44.5 26 Feb     2.5 27 Jun 342.0 603.2 lowest 57%
Medina Research Centre 25.5 +1.3 43.8 17 Jan 12.1 -0.1 0.0 26 Jun 487.1 762.6 v low 64%
Pearce RAAF 26.3 +1.2 44.2 18 Jan 11.6 -0.6 -1.9 4 Jul 347.2 658.5 lowest 53%
Perth Airport 26.0 +1.6 43.2 18 Jan 11.9 -0.2 -1.0 3 Jul 483.2 774.2 v low 62%
Perth Metro 25.3 +0.8 42.9 17 Jan 12.3 -0.3 -0.6 26 Jun 503.8 852.6 v low 59%
Rottnest Island 22.4 +0.4 41.1 17 Jan 15.7 +0.1 7.9 10 Jul 476.2 563.2 low 85%
Swanbourne 24.9 +1.1 42.9 17 Jan 13.5 -0.3 2.9 25 Jun 584.4 720.0 v low 81%
South Coast (district 09A)
Albany 19.8 +0.3 38.9 18 Jan 12.7 +1.1 5.5 10 Jun 742.2 929.7 v low 80%
Albany Airport 20.5 +0.3 40.7 18 Jan 10.4 -0.1 0.9 10 Jun 674.6 794.4 low 85%
Bridgetown Comparison 23.7 +1.3 41.0 18 Jan 8.4 +0.4 -2.6 10 Jun 399.9 823.8 lowest 49%
Bunbury 23.8 +0.9 40.6 17 Jan 10.4 -0.5 -0.3 3 Jul 484.4 724.8 v low 67%
Busselton 23.3 +0.6 37.5 17 Jan 10.8 -0.5 1.5 3 Jul
Busselton Aero 23.6 +0.7 39.4 17 Jan 9.4 -0.8 -0.1 10 Jun 435.6 704.3 v low 62%
Cape Leeuwin 20.6 +0.9 38.3 12 Mar 14.7 +0.6 6.9 10 Aug 625.0 970.0 v low 64%
Cape Naturaliste 22.0 +1.4 37.8 17 Jan 12.9 +0.2 5.9 24 Jun 574.0 812.1 v low 71%
Collie East 24.3   40.4 18 Jan 8.1   -3.0 11 Jun 390.0
Donnybrook 24.5 +1.4 41.5 17 Jan 10.3 +0.6 0.0 3 Jul 511.3 975.9 lowest 52%
Dwellingup 23.6 +1.9 40.4 18 Jan 9.3 -0.2 -2.0 25 Jun 589.7 1245.2 lowest 47%
Esperance 22.4 +0.6 46.9 6 Jan 12.2 +0.2 4.2 26 Jun 494.8 615.6 low 80%
Esperance Aero 22.5 +0.5 46.4 6 Jan 11.2 0.0 3.5 3 Jul 532.6 564.6 average 94%
Harvey 24.6   41.2 17 Jan 11.1   1.0 30 Jun 481.2 834.9 v low 58%
Hopetoun North 21.8 -0.4 48.0 6 Jan 11.6 +0.2 3.4 11 Jun 461.6 487.9 low 95%
Jarrahwood 23.7 +1.4 40.5 17 Jan 7.9 -0.7 -3.2 10 Jun 526.8 929.5 lowest 57%
Mandurah 23.9   40.1 25 Dec 14.4   4.9 25 Jun 451.4
Manjimup 21.7 +1.4 40.8 18 Jan 9.7 +0.1 2.0 3 Jul 549.0 1006.6 lowest 55%
North Walpole 20.5   38.5 12 Mar 11.6   3.7 11 Jun
Pemberton 21.6 +1.4 38.9 17 Jan 10.3 +0.2 2.6 11 Jun 669.1 1191.4 lowest 56%
Rocky Gully 21.2 +0.5 39.7 6 Jan 9.3 -0.3 1.4 25 Jun 475.2 683.5 v low 70%
Shannon 20.7 +0.3 38.5 18 Jan 9.5 -0.1 1.8 9 Aug 520.6 1021.7 v low 51%
Witchcliffe 21.9 +0.8 39.3 17 Jan 10.1 -0.5 -0.7 10 Jun 857.2 935.5 average 92%
North Central (district 10)
Cunderdin Airfield 26.8 +1.1 46.0 19 Jan 9.9 -0.4 -3.7 5 Jul 167.2 300.5 v low 56%
Merredin 26.5 +1.6 45.2 6 Jan 11.4 +0.1 -2.5 27 Jun 179.4 325.2 v low 55%
Northam 26.8 +1.5 44.5 18 Jan 10.2 -0.7 -3.5 26 Jun 232.6 428.6 v low 54%
York 26.5 +1.2 44.5 18 Jan 8.7 -0.8 -4.2 7 Jul 221.2 378.2 v low 58%
South Central (district 10A)
Brookton 25.1 +0.9 42.7 18 Jan     -2.9 26 Jun 256.4 451.8 v low 57%
Corrigin 25.1 +1.4 43.5 9 Jan 9.8 -0.1 -4.0 26 Jun 166.5 372.9 lowest 45%
Hyden 26.5 +1.5 47.0 9 Jan 9.7 -0.2 -4.0 25 Jun 142.1 338.6 lowest 42%
Jacup 22.4 +0.6 46.1 6 Jan     0.8 23 Aug 364.6 455.5 low 80%
Katanning 22.9 +0.6 42.4 18 Jan 9.2 -0.2 -0.2 25 Jun
Katanning Comparison 23.3 +1.2 42.2 18 Jan 9.0 -0.3 -2.4 11 Jun 287.9 477.7 v low 60%
Lake Grace 24.0 +0.6 44.4 6 Jan 9.9 -0.3 -1.3 23 Aug 170.6 325.1 v low 52%
Lake Grace Comparison 24.1 +0.8 43.8 6 Jan 10.2 0.0 -1.3 23 Aug 155.6 350.2 lowest 44%
Narembeen 26.4 +1.3 45.3 9 Jan 10.5 -0.1 -3.2 3 Jul 180.4 330.7 v low 55%
Narrogin 23.7 +1.4 42.2 18 Jan 9.4 0.0 -1.6 25 Jun 291.3 495.0 v low 59%
Newdegate Research Station 24.0 +0.8 45.7 6 Jan 8.2 -0.5 -2.4 10 Sep
Ongerup 22.5 +0.8 43.0 18 Jan 9.5 -0.2 -0.4 25 Jun 293.6 384.8 low 76%
Pingelly 24.6 +1.4 42.6 18 Jan 10.2 -0.2 -2.5 3 Jul 287.2 445.9 v low 64%
Wagin 23.9 +1.0 43.1 18 Jan 9.3 -0.4 -1.2 11 Jun 246.8 433.4 v low 57%
Wandering 24.6 +1.0 43.6 18 Jan     -2.9 11 Jun 277.4 488.9 v low 57%
Eucla (district 11)
Balladonia 25.1 +0.5 45.6 19 Feb 10.1 +0.3 -2.3 26 Jun 227.0 261.9 average 87%
Eucla 22.8 0.0 43.6 7 Feb 12.3 +0.1 1.8 5 Jul 448.8 271.3 highest 165%
Eyre 23.6 +0.8 45.6 7 Jan 9.8 -1.0 -6.8 11 Aug 262.4 306.8 low 86%
Forrest 25.4 -0.8 44.4 29 Dec 11.1 +0.2 0.0 11 Aug 276.2 241.8 average 114%
Red Rocks Point 21.9   44.1 7 Jan 12.9   2.1 11 Aug 315.2
South East (district 12)
Bulga Downs 29.5   46.5 15 Feb 14.0   -1.7 2 Jul 243.4 229.5 average 106%
Kalgoorlie-Boulder Airport 25.9 +0.6 45.0 20 Jan 12.4 +0.7 -1.6 27 Jun 165.6 262.7 low 63%
Laverton Aero 27.2 +0.4 44.1 20 Jan 14.6 +0.8 -0.3 4 Jul 243.2 280.6 average 87%
Leinster Aero 28.4 +0.3 44.8 20 Jan 15.0 +0.4 -0.5 2 Jul 258.0 260.7 average 99%
Leonora 28.1 +0.2 46.5 20 Jan 14.5 +0.6 0.5 28 Jun 220.2 234.0 average 94%
Leonora Aero 28.0   45.5 20 Jan 14.8   -0.9 2 Jul 192.6
Munglinup West 23.0   47.6 6 Jan 10.4   2.0 3 Jul
Norseman Aero 25.4 +0.4 44.8 6 Jan 9.6 -0.2 -6.0 27 Jun 183.4 294.0 v low 62%
Southern Cross Airfield 26.4 +0.6 45.7 6 Jan 10.3 +0.2 -4.2 27 Jun 151.4 303.6 v low 50%
North East (district 13)
Giles Meteorological Office 28.8 -0.5 42.5 1 Jan 15.9 0.0 2.3 14 Jul 337.4 283.3 high 119%
Telfer Aero 34.6 +0.5 46.5 1 Jan 20.6 +1.2 7.0 11 Aug 246.0 359.6 average 68%
Warburton Airfield 29.8 0.0 45.3 30 Dec 16.2 +1.6 0.1 14 Jul 183.2 240.2 average 76%
Wiluna 30.0 +0.9 45.4 31 Dec     -0.5 2 Jul 229.1 254.9 average 90%

Notes

A Annual Climate Summary is prepared to list 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. Later information, including data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review, usually published in the fourth week of the month.

This statement has been prepared based on information available at 12 pm on Tuesday 4 January 2011. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Averages 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.
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.

Records in this summary are based on sites with at least 30 years of data.

For PDF files of Perth Metro climate statistics for other months, please click here for extremes and here for averages.

Further information

Media
(03) 9669 4057
Enquiries