Western Australia in 2011: Wettest year on record

  • Rainfall: Wettest year on record for WA, near average for southwest WA
  • Maximum temperature: Near average for WA; 3rd warmest year on record for southwest WA.
  • Minimum temperature: Near average for WA; warmest year on record for southwest WA.

Rainfall

Annual rainfall in WA in 2011 was above average to very much above average over most of WA, with areas of highest on record in the Kimberley and in central and southeastern parts of the state. Below average rainfall was confined to the Southwest district, western parts of the Lower West and Central West, and eastern parts of the Southeast Coastal district (see the annual rainfall totals & deciles).

When averaged across the state, WA observed its wettest year on record in 2011 with a state-wide average of 601 mm, breaking the record of 596 mm observed in 2000 (comparable records commenced in 1900). The original release of the Annual Climate Summary for WA on 4 January 2011 indicated that 2011 was WAs 2nd wettest year on record, with an annual total of 595 mm, however additional rainfall data has been received since then and has elevated 2011 to the wettest year on record in WA. Spatially averaged rainfall data showed that in the Lower Southwest (southwest of a line from Jurien Bay to Bremer Bay), annual rainfall was in the near average range, whilst in the Southwest Land Division (SWLD), annual rainfall in 2011 was above average.

The unusually wet conditions across most of WA in 2011 were primarily the result of a very active monsoon season during the first four months of 2011, aided by one of the strongest La Ninas on record and exceptionally warm Indian Ocean temperatures. Summer 2010-11 saw the second wettest summer on record for WA, and was followed by very much above average autumn rainfall. Although the La Nina weakened in late autumn, and winter rainfall for WA as a whole was near average, the La Nina redeveloped in early spring, with several middle level troughs bringing relatively frequent thunderstorms to much of the state in spring and early December. Significant rainfall events with resultant widespread crop damage occurred late in the season in the SWLD, and the second wettest spring on record in WA was registered.

A number of sites recorded their wettest day on record during 2011, most notably due to rainfall events in February and March in the Kimberley, Goldfields and Eucla. The highest daily fall in WA in 2011 was 388.6 mm at Kuri Bay on 11 January, the result of a very active monsoon trough, with the daily total probably higher than observed given that the rainfall gauge overflowed before the observer was able to check the final total. Kuri Bay went on to record the highest January rainfall total on record for WA, partly as a result of this event, with 1540.4 mm. The second highest daily fall during 2011 was 351.0 mm at Durack Range in the Kimberley on 14 March, the result of an intense monsoonal event that brought significant flooding to the region. Several sites registered their wettest year on record, mostly in the Kimberley, due to above average rainfall in the early part of the year, but also in the southern Gascoyne and Great Southern, due to the wet spring and wet December. The wettest location in the state in 2011 was Doongan with 2458.1 mm, which is more than double its annual average rainfall, and in fact this is the highest annual rainfall on record in WA, breaking the previous record of 2380.6 mm observed at Kimberly Coastal Camp in 2000. Gibb River in the Kimberley was also very wet during 2011, recording a total of 2136.2 mm, which is the 7th wettest year on record in WA, whilst Theda with 2114.5 mm observed the 9th wettest year on record in WA.

Maximum temperature

Maximum temperatures in WA during 2011 were above average to very much above average in western and southern parts of the state, with areas of hottest on record in western parts of the Central West, Lower West, and Southwest districts. In contrast, most of the Kimberley, central and eastern parts of the Pilbara, the northern and western Interior, and Goldfields were below to very much average in terms of daytime maximum temperature, with areas of lowest on record in the east Kimberley (see the annual mean maximum temperature averages & deciles).

Averaged across the state as a whole, the annual mean maximum temperature was 0.2 °C below the long-term average, and so in the close to normal range, however the Lower Southwest observed its third warmest year since comparable records commenced in 1910, with a mean 1.1 °C above the long-term average. The Lower Southwest experienced above average daytime temperatures for most months of the year, as well as the second hottest autumn, and the eighth warmest winter. To highlight the significance of the warm year in the Southwest district, a number of stations with over 100 years of record registered their warmest ever year.

The hottest day of the year in WA was 22 December when Roebourne in the Pilbara recorded 49.4 °C, a December record for WA, the 5th hottest temperature on record in WA, and the 2nd hottest December day on record for Australia.

Minimum temperature

Minimum temperatures in 2011 were above average to very much above average across western, cental, and southern WA, with areas of highest on record over much of the SWLD and adjacent Gascoyne and Eucla. Conversely, below to very much below average mean minima were observed in much of the Kimberley and neighbouring parts of the inland Pilbara and northern Interior, with areas of lowest on record in the east Kimberley (see the annual mean minimum temperature averages & deciles).

Averaged across the state as a whole, the annual mean minimum temperature was just 0.2 °C above the long-term average. However, the Lower Southwest observed its warmest year on record in terms of the mean minimum temperature, with a mean 1.2 °C above the long-term average, breaking the previous record set in 1963 by 0.3 °C. The Lower Southwest experienced above average night-time temperatures for most months of the year, including the equal warmest February, and fourth warmest December, as well as the seventh warmest autumn, and ninth warmest winter since comparable records commenced in 1950. Many sites in the SWLD registered their highest annual mean minimum temperature on record, whilst Cape Leeuwin, Bridgetown, Cape Naturaliste, and Donnybrook, all in the Southwest district, broke their annual record with more than 100 years of temperature observation.

Despite observing its coolest year on record in terms of overnight temperature, Wyndham in the east Kimberley was still the warmest location overnight in WA in 2011 with a mean minimum of 21.4 °C

Notable events

  • Severe Tropical Cyclone Bianca moved across the north Kimberley as a tropical low on 24 and 25 January then developed into a tropical cyclone and tracked along the Pilbara coast on 26 and 27 January before increasing to category 4 strength off the WA west coast then weakening as it approached Perth on 30 January. The tropical low brought significant rain to the Kimberley, whilst strong winds and siginificant rainfall was reported near the Pilbara coast though TC Bianca remained offshore.
  • Severe thunderstorms formed on the afternoon of 28 January, tracked through the Kimberley, Pilbara, and Gascoyne, before becoming an organised squall line on the morning of the 29th and causing widespread damage due to severe wind gusts through the western Central Wheat Belt, and western Great Southern.
  • Kuri Bay in the west Kimberley recorded 1540.4 mm of rainfall during January 2011, the highest total rainfall recorded in a month in WA.
  • Strong and gusty easterly winds between 5 and 7 February drove fires to burn out of control to the east of Perth, near Red Hill, in the Swan Valley, and Roleystone and Kelmscott to Perth’s east. Over 100 homes were destroyed or partially damaged in the Kelmscott and Roleystone areas.
  • Severe Tropical Cyclone Carlos, which formed over the Top End of the NT and caused very heavy rainfall in Darwin, moved through the Kimberley and reformed off the Kimberley west coast. TC Carlos brought heavy rainfall as it moved along the Pilbara coast, passing near Karratha on 22 February, and Onslow and Exmouth on 23 February, whilst a tornado in an outer rainband of the TC moved over Karratha CBD on 21 February and caused extensive damage.
  • During the week ending 14 March, an intense monsoonal burst caused extensive flooding in the east Kimberley region of WA.
  • The passage of a cold front across southwest WA on 29 May resulted in a tornado passing through in Bunbury and significant damage to several houses in the suburb of Usher.
  • Heavy rainfall centred on the Great Southern district on the afternoon of 3 November brought widespread falls of over 40 mm, and some falls over 60 mm, causing significant crop damage in the region.
  • Bushfires in the the Margaret River region from 23 to 26 November destroyed 41 homes and holiday chalets, and damaged a number of other homes whilst burning through over 3,000 hectares.
  • Two significant rainfall events in the SWLD in December as a result of middle levels troughs over the region caused localised damage, particularly to grain crops, and some flash flooding. The events followed a very wet spring, which had already brought significant crop damage to some parts of the SWLD. Rainfall totals of just over 100 mm were recorded in the northeast Great Southern on 6 and 7 December and were some of the highest December falls on record for the SWLD. This was followed by an event on 12 and 13 December that brought widespread heavy rainfall to large parts of the SWLD. Williams in the northwest Great Southern recorded 125.6 mm, which is the highest one day rainfall total recorded in the SWLD in December. Signifcant local floooding was reported in the Williams and Narrogin region as a result of the severe thunderstorms. See the Special Climate Statement Very heavy rainfall in southern WA for more information.
  • Extremely hot weather was observed in the Pilbara from 20 to 25 December, with numerous sites observing daily maxima over 47 °C. The December maximum temperature record for WA was broken on three consecutive days, with Roebourne (49.4 °C on the 21st), Roebourne Airport (49.0 °C on the 21st), Onslow (49.2 °C on the 22nd) and Learmonth (48.9 °C on the 23rd), all surpassing the previous December record of 48.8 °C set at Mardie on 26 December 1986. The 49.4 °C at Roebourne was also the 2nd hottest December day in Australia, just 0.1 °C behind the 49.5 °C recorded at Birdsville in Queensland on 24 December 1972, as well as the 5th hottest day on record in WA.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in 2011
Hottest day 49.4 °C at Roebourne on 21 Dec
Warmest days on average 34.5 °C at Fitzroy Crossing Aero
Coolest days on average 20.4 °C at Albany
Coldest day 8.9 °C at Bulga Downs on 10 & 11 Jul
Coldest night -4.1 °C at Eyre on 24 Sep
Coolest nights on average 9.5 °C at Jarrahwood
9.5 °C at Newdegate Research Station
Warmest nights on average 23.5 °C at Varanus Island
21.4 °C at Wyndham
Warmest night 33.2 °C at Wittenoom on 22 Dec
Wettest overall 2458.1 mm at Doongan
Driest overall 257.0 mm at Gascoyne Junction
Wettest day 388.6 mm at Kuri Bay 11 Jan
Highest wind gust 139 km/h at Varanus Island on 22 Feb

Record highest annual daily rainfall
Highest daily rainfall
in 2011 (mm)
Previous annual
wettest
Years of
record
Laverton 120.2 on 17 Feb 92.6 on 24 Jan 2000 111
Yundamindra 126.0 on 17 Feb 101.6 on 1 Jan 1955 110
Warmun 181.1 on 14 Mar 167.9 on 13 Apr 1910 104
Hyden 105.0 on 7 Dec 100.3 on 2 Jan 1966 83
Eyre 81.2 on 17 Mar 75.8 on 17 Mar 2000 67
Amrista Park 109.0 on 7 Dec 101.6 on 17 Feb 1970 56
Bedford Downs 257.0 on 14 Mar 212.5 on 4 Feb 1974 46
Beebyn 227.0 on 19 Feb 111.8 on 9 Mar 1926 44
Charnley River 233.0 on 5 Apr 202.0 on 21 Jan 1986 44
Tawarri West 102.0 on 19 Feb 82.6 on 27 May 1999 37
Mooloo Downs 86.0 on 11 Feb =86.0 on 21 Jun 1980 32
Sophie Downs 160.0 on 14 Mar 134.2 on 20 Feb 2001 32
Kybo 102.0 on 24 Feb 94.6 on 1 Jan 2006 30



Record highest total annual rainfall
Total rainfall
for 2011 (mm)
Previous annual
wettest
Years of
record
Annual
average
Warmun 1540.2 1342.7 in 2000 101 722.4
Fossil Downs 1087.3 1048.8 in 1984 95 532.3
Gibb River 2136.2 1368.4 in 1974 81 785.0
Carnegie 524.4 455.0 in 1967 56 234.5
Amrista Park 521.9 503.4 in 1963 54 357.9
Paynes Find 579.6 539.2 in 1992 44 291.2
Mount Barnett 1547.4 1315.8 in 2007 41 908.3
Yulmbu 1752.8 994.4 in 2002 41 661.5
Kojonolokan Hills 607.5 518.8 in 2005 38 412.4
Theda 2114.5 1684.1 in 2008 37 1261.3
Mount Elizabeth 1928.4 1301.3 in 2007 36 990.6



Record highest annual temperature
Highest temperature
in 2011 (°C)
Previous annual
warmest
Years of
record
Annual
average
Salmon Gums Res.Stn. 46.3 on 28 Jan 45.7 on 6 Jan 2010 76 23.4
Giles Meteorological Office 44.8 on 28 Jan = 44.8 on 27 Dec 1986 56 29.3
Roebourne 49.4 on 21 Dec 49.1 on 18 Feb 1998 55 34.0
Onslow Airport 49.2 on 22 Dec 48.9 on 11 Jan 2008 48 31.9
Learmonth Airport 48.9 on 23 Dec = 48.9 on 2 Jan 2010 37 31.8



Record highest annual mean daily maximum temperature
Mean daily maximum
temperature
for 2011 (°C)
Previous annual
warmest
Years of
record
Annual
average
Cape Leeuwin 21.2 20.9 in 1983 114 19.7
Bridgetown Comparison 23.8 = 23.8 in 1930 109 22.4
Cape Naturaliste 22.8 22.6 in 1999 107 20.6
Donnybrook 24.6 24.5 in 1972 106 23.1
Manjimup 22.0 21.7 in 2010 70 20.3
Geraldton Airport Comparison 27.2 26.9 in 1988 66 25.9
Perth Airport 26.1 26.0 in 2010 66 24.4
Pemberton 22.1 21.5 in 2010 63 20.3



Record lowest annual mean daily maximum temperature
Mean daily maximum
temperature
for 2011 (°C)
Previous annual
coolest
Years of
record
Annual
average
Halls Creek Airport 31.6 31.9 in 1974 63 33.6
Mardie 32.6 32.9 in 1992 52 33.9
Warmun 33.0 33.2 in 1974 46 35.1
Wyndham 33.7 34.2 in 2006 40 35.6



Record highest annual daily minimum temperature
Highest daily minimum
temperature
in 2011 (°C)
Previous annual
warmest
Years of
record
Annual
average
Eucla 30.7 on 30 Jan 30.2 on 26 Feb 2009 55 12.2



Record lowest annual temperature
Lowest temperature
in 2011 (°C)
Previous annual
coolest
Years of
record
Annual
average
Wyndham 8.3 on 14 Jun 8.6 on 29 Jun 2004 44 23.2
Telfer Aero 2.1 on 14 Jun 2.5 on 19 Jun 1976 38 19.4



Record highest annual mean daily minimum temperature
Mean daily minimum
temperature
for 2011 (°C)
Previous annual
warmest
Years of
record
Annual
average
Cape Leeuwin 15.3 14.9 in 1996 114 14.1
Onslow 20.5 20.4 in 1998 114 18.0
Bridgetown Comparison 9.7 9.5 in 1983 108 8.0
Cape Naturaliste 14.0 13.7 in 1983 107 12.7
Donnybrook 11.7 11.2 in 1983 105 9.7
Albany 13.1 12.8 in 2010 91 11.7
Balladonia 11.2 10.8 in 1999 80 9.8
Dwellingup 11.0 10.6 in 1963 70 9.5
Kalgoorlie-Boulder Airport 12.7 12.6 in 1991 68 11.7
Pemberton 11.7 11.2 in 1963 62 10.1
Mullewa 14.9 14.3 in 1963 60 13.1
Eucla 13.1 12.8 in 1961 51 12.2
Pearce RAAF 13.8 13.2 in 1967 48 12.2
Albany Airport 11.2 11.1 in 1978 45 10.5
Esperance 12.8 12.6 in 1983 41 12.0
Beverley 11.5 10.9 in 1992 40 10.2
Ongerup 10.5 = 10.5 in 1983 40 9.7
Badgingarra Research Stn 13.3 12.7 in 1999 38 11.8
Pingelly 11.4 11.1 in 1978 38 10.4
Wagin 10.5 = 10.5 in 1991 35 9.7
Hyden 11.5 10.4 in 2003 34 9.9
Kalbarri 16.2 15.5 in 1996 34 14.5



Record lowest annual mean daily minimum temperature
Mean daily minimum
temperature
for 2011 (°C)
Previous annual
coolest
Years of
record
Annual
average
Wyndham 21.4 21.9 in 1976 41 23.2



Maps
Observed Anomaly Decile 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 for all of Australia Map of Anomaly in mean maximum temperature for all of Australia Map of Decile rank of mean maximum temperature
Mean
daily
minimum
temperatures
Map of Mean minimum temperature for all of Australia Map of Anomaly in mean minimum temperature for all of Australia Map of Decile rank of mean minimum temperature

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


Month by month
An active monsoon for much of the January 2011 over the Kimberley resulted in Kuri Bay observing 1540.4 mm of rainfall, the wettest month on record for WA. Elsewhere, rainfall was mostly above average and the Lower Southwest (southwest of a line from Jurien Bay to Bremer Bay) saw its 5th wettest January on record mainly the result of a cold front over the region interacting with tropical moisture on the 5th, and a line of storms moving through the region on the 29th. Severe Tropical Cyclone Bianca brought heavy rainfall to the Pilbara coast late in January. Monthly mean maximum temperatures were above to very much above average in much of the southern half of WA as well as through the Interior, where some sites recorded one of the hottest Januarys on record. Forrest in the Eucla recorded 48.4 C on the 30th, the third highest temperature recorded in WA in January 2011. In contrast, northern coastal parts of the state observed below to very much below average daytime temperatures, the result of an active monsoon. The mean daily minimum temperature for WA during January 2011 was the highest on record, with numerous sites in WA recording their highest January mean minimum.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
Rainfall rankMaximum temperature rankMinimum temperature rank
February 2011 was the second wettest February on record across WA as a whole, with areas of highest on record reported in the Kimberley, Pilbara, Gascoyne, Central West, Central Wheat Belt, Goldfields, Interior and Eucla. Tropical Cyclone Dianne formed off the northwest coast during the middle of the month and remained offshore but contributed to heavy rainfall in northwest and central parts of WA. Tropical Cyclone Carlos became the first TC to make landfall on the northwest coast of WA in the 2010/11 season when it formed near Darwin before crossing the Kimberley and moving parallel with the Pilbara coast. February 2011 ranked as the third coolest in terms of daytime temperature, with most of WA away from the west coast observing below to very much below average daytime temperatures. In contrast, the west coast of WA and adjacent inland parts saw above to very much above average daily maximum temperatures, with a few sites in western parts of the Lower West and Southwest observing their hottest month on record due to consistently hot days and a lack of cooling sea breezes. Western and southern WA experienced above to very much above average overnight minima with areas of record high mean monthly minimum temperature in the southwest Gascoyne and Southwest district. The Lower Southwest observed its equal warmest February on record for minimum temperatures when averaged across the region.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
March rainfall was very much above average over much of the eastern half of the state, with extreme rainfall causing significant flooding in the east Kimberley during the middle of the month. Partly as a result of the rain and cloudy conditions over much of the east and north of the state, WA observed its fifth coolest March on record in terms of daytime maximum temperature. In contrast though, the Lower Southwest observed its third hottest March on record in terms of daytime temperature, as well as its fourth warmest March on record in terms of overnight temperatures.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
April saw heavy rainfall in the north Kimberley during the first half of the month due to an active monsoon trough, whilst a tropical low brought heavy rainfall to the far north Kimberley as it developed into Tropical Cyclone Errol on the 15th, well off the WA coast. Rainfall for the Lower Southwest was near average, mainly due to cold fronts over the Easter period late in the month, whilst the Lower Southwest continued its warm start to the year, observing its fourth hottest April on record in terms of maximum temperature. Both the maximum and minimum temperature patterns across WA in April were similar with above average temperatures experienced in western and southern parts of the state, but below average temperatures recorded in the Kimberley and neighbouring districts.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
Rain over WA during May 2011 was patchy, with areas of above and below average rainfall scattered across the state. A cold front brought the first significant rainfall to the SWLD on the 20th, followed by another front on the 29th and 30th, however, the fronts also brought severe winds with damage reported in southern parts of Perth and in parts of Bunbury. In the north, a cloudband brought significant rainfall to the Pilbara during the middle of the month. Both maximum and minimum temperatures were below average during May 2011 when averaged across the state as a whole. However, the Lower Southwest region experienced above average maximum temperatures and near average minimum temperatures.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
Despite several strong cold fronts moving through southern Western Australia during June 2011, rainfall totals were generally near to or below average across the SWLD, with very much below average rainfall notable in the Southeast Coastal district. In contrast, wetter than normal conditions were experienced in the west Pilbara, Eucla, southern Interior and parts of the Goldfields, mainly due to cloudbands moving through the state during the early part of the month. When averaged across WA as a whole, rainfall was near average. Both maximum and minimum temperatures were below normal in the northeast of the state, with a particularly cool period during the middle of the month as relatively cool air moved over northern WA from the southeast. In contrast, southern and western parts of WA generally observed above average maximum and minimum temperatures.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
July saw a number of strong cold fronts cross southwest WA, particularly in the latter part of the month, bringing heavy rainfall and severe winds. Despite this, rainfall totals for the month were generally close to average throughout the Lower Southwest. For WA as a whole, rainfall was above average, with central parts of the state experiencing wetter than normal conditions due to a number of cloudbands moving through the region. The coldest day of 2011 was observed during mid-July, with Bulga Downs in the southern Gascoyne observing 8.9 °C on both the 10th and 11th due to a thick mid-level cloudband. Mean minima were above average across most of WA, except in parts of the Southwest and Kimberley. WA observed its fourth warmest July in terms of overnight minima, mainly as a result of persistent cloud cover over much of the state during the month.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
August rainfall across WA as a whole was near average, but areas of above average rainfall in central parts of the state contrasted with areas of below average rainfall in the east and south. Widespread rainfall was evident over much of southern WA in the first few days of August due to a strong westerly flow, while strong cold fronts during the middle of the month brought strong winds and moderate to heavy rainfall to southwest and central WA. A strong cold front crossed the SWLD on the 21st and 22nd, with a number of locations in the Southwest district breaking their highest daily rainfall records for August. Maximum temperatures were above to very much above average across most of WA during August 2011, with the month ranking as the 4th warmest on record for the state, as well as equal 3rd warmest on record for the Lower Southwest. Overnight temperatures were above to very much above average across much of western, central and southern WA, but below to very much below average in most of the Kimberley.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
Rainfall across WA during September 2011 was mixed with areas of above average rainfall in the central and northern SWLD, Goldfields, Gascoyne, west Pilbara and west Kimberley, and below average rainfall in the Interior, southeast Pilbara, northeast Gascoyne, and South and Southeast Coastal districts. A number of cold fronts moved through the south of the state during the month, the most significant of these occurring on the 18th with heavy rainfall observed in the SWLD and severe wind gusts causing damage in the Lower West and Goldfields. Overnight temperatures were below average across large parts of central and northern WA, with particularly cool nights occurring in the north of the state during the middle of the month due to a very strong slow moving high to the south. Above average overnight minima were restricted to parts of the SWLD coast and the Eucla.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
October was a wet month across most of the state, but particularly in the Goldfields and parts of the SWLD where numerous October monthly rainfall records were broken. The month was the 3rd wettest October for WA as a whole, whilst only parts of the Eucla, Southwest and Lower West, northern Gascoyne, and Pilbara, recorded below average rainfall for the month. Maximum temperatures were near average across most of WA, although areas of above to very much above average maxima were observed in the western coastal strip south of Shark Bay. Below average maxima were experienced in southern parts of the Kimberley, the northern Interior, parts of the Pilbara coast, southern Gascoyne, and Goldfields. Minimum temperatures were above average across most of southern and central WA, with a number of sites in the SWLD recording their warmest October on record, and the Lower Southwest registering its 3rd warmest October since comparable records commenced in 1950. Only in the Kimberley were below average minima recorded.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
November rainfall was above to very much above average for most of WA and a number of sites in the Kimberley, Pilbara, Gascoyne, Central Wheat Belt, Great Southern, Southeast Coastal, and Goldfields registered their wettest November on record. Below average rainfall was mainly confined to the Eucla, and small areas of the southern Goldfields, northern Central West, and west Kimberley. When averaged across the state, November 2011 was the fifth wettest November on record for WA, whilst November rainfall for the Lower Southwest ranked as tenth wettest on record. Maximum temperatures were above average in parts of coastal WA, however most central and northern parts saw below average maxima and a similar pattern was evidint in mean minimum temperatures across the state.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
Rainfall in WA during December was above to very much above average for most of the SWLD, adjacent parts of the Goldfields, and the southeast Gascoyne, with numerous sites in the SWLD registering their wettest December on record, mainly due to extremely heavy rainfall events on the 6th and 12th. Above to very much above average rainfall was also observed in the Interior, inland Kimberley, where the highest rainfall totals for December in WA were recorded, and the coastal Eucla. Below to very much below average rainfall was evident through much of the Pilbara and northwest Gascoyne, the coastal Kimberley, and inland Eucla. Mean daily maximum temperatures in WA during December 2011 were below to very much below average over eastern parts of the SWLD, the Goldfields, western Eucla, southern Interior, and coastal parts of the Pilbara. Above to very much above average maxima were observed along the west coast of WA, extending into the northern Gascoyne and inland Pilbara, and in western and northern parts of the Kimberley. Mean daily minimum temperatures in WA in December 2011 were above to very much above average over large parts of western and southern WA, as well as in the west Kimberley, and several sites in western parts of the SWLD registered record high December mean minima. Below to very much below average overnight temperatures were reported in the central and southeast Kimberley, and northern and central Interior, and when averaged across the state, overnight temperatures in WA in December 2011 were below average. However, the Lower Southwest observed its 4th warmest December on record.
Map of decile rank of rainfall Map of Decile rank of mean maximum temperature Map of Decile rank of mean minimum temperature
Rainfall rankMaximum temperature rankMinimum temperature rank

Summary statistics for 2011
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean
for
2011
Diff
from
average
Highest
for
2011
Mean
for
2011
Diff
from
average
Lowest
for
2011
Total
for
2011
Average
annual
total
Rank
of
2011
Fraction
of annual
average
North Kimberley (district 01)
Doongan 31.4 -1.7 40.2 12 Oct 17.2 -1.3 2.4 15 Jun 2458.1 1205.1 v high 204%
Kalumburu 32.7 -1.6 38.5 26 Dec 19.2 -1.2 4.5 14 Jun 1827.0 1218.8 v high 150%
Wyndham 33.7 -1.9 42.5 12 Oct 21.4 -1.8 8.3 14 Jun 1548.8 832.0 v high 186%
Wyndham Aero 34.2 -1.7 44.0 12 Oct 21.1 -1.3 6.9 15 Jun 1397.4 839.7 v high 166%
East Kimberley (district 02)
Argyle Aerodrome 32.8 -1.9 42.3 12 Oct 20.7 -1.5 8.3 14 Jun
Halls Creek Airport 31.6 -2.0 40.9 26 Dec 18.8 -1.2 5.3 14 Jun 1006.0 566.0 v high 178%
Warmun 33.0 -2.1 42.0 12 Oct 19.2 -1.1 4.7 14 Jun 1540.2 722.4 highest 213%
West Kimberley (district 03)
Bidyadanga                 674.6 509.8 high 132%
Broome Airport 32.0 -0.2 41.0 26 Nov 20.7 -0.5 5.9 15 Jun 831.8 606.2 high 137%
Curtin Aero 34.3 -1.2 45.1 1 Dec 20.1 -1.0 8.9 3 Jun 1294.2 846.4 v high 153%
Derby Aero 33.5 -1.0 44.9 1 Dec 20.4 -1.2 6.5 16 Jun 1018.6 686.9 v high 148%
Fitzroy Crossing Aero 34.5 -1.6 44.2 1 Dec 19.0 -1.2 4.7 13 Jun 975.4 720.4 high 135%
West Roebuck 33.5   42.3 26 Nov 19.4   4.3 14 Jun 967.4 859.4 high 113%
De Grey (district 04)
Karratha Aero                 765.8 296.2 v high 259%
Legendre Island 29.5   37.4 19 Mar 22.7   13.9 15 Jun
Mandora                 513.9 374.7 high 137%
Port Hedland Airport 32.5 -0.7 43.0 20 Dec 19.6 +0.2 6.5 15 Jun 551.8 313.3 v high 176%
Roebourne 33.6 -0.4 49.4 21 Dec         489.8 312.0 high 157%
Roebourne Aero 33.2   49.0 21 Dec 19.4   6.1 15 Jun 557.0 256.7 high 217%
Fortescue (district 05)
Learmonth Airport     48.9 23 Dec         402.8 253.8 high 159%
Mardie 32.6 -1.3 48.5 21 Dec 19.2 +0.5 7.3 15 Jun 855.4 275.8 v high 310%
Onslow 31.4 +0.1 48.7 22 Dec 20.5 +2.5 11.1 22 Jun 557.9 272.6 v high 205%
Onslow Airport 31.7 -0.2 49.2 22 Dec 20.1 +1.2 10.6 17 Jun 624.2 324.9 v high 192%
Wittenoom 32.2 -0.7 46.0 21 Dec 19.2 -0.5 5.8 15 Jun 566.0 459.4 high 123%
West Gascoyne (district 06)
Carnarvon Airport 28.6 +1.4 42.4 27 Dec 18.0 +0.8 6.5 5 Aug 398.8 231.3 v high 172%
Denham 27.8 +1.2 41.0 27 Dec 19.5 +1.9 9.3 7 Jul 341.0 224.9 high 152%
Emu Creek Station 33.6 -0.1 48.2 24 Dec         298.2 299.1 average 100%
Shark Bay Airport 29.3 +0.4 43.1 1 Jan 17.2 +1.0 7.3 7 Jul 406.6 212.1 v high 192%
East Gascoyne (district 07)
Newman Aero                 408.0 322.0 average 127%
Paraburdoo Aero 32.9 -0.5 46.9 25 Dec 18.6 +0.6 5.9 3 Jul 393.0 319.0 high 123%
Murchison (district 07A)
Meekatharra Airport 28.7 -0.2 43.4 23 Dec 16.1 +0.2 2.7 3 Jul 367.6 238.1 v high 154%
Mount Magnet Aero 27.8 -0.6 44.0 1 Jan 15.5 +0.5 1.7 6 Jul 434.2 263.9 v high 165%
North Coast (district 08)
Dalwallinu 26.2 0.0 42.9 2 Jan 12.6 +1.0 1.9 28 Sep 395.4 294.2 v high 134%
Dalwallinu Comparison 26.4 +0.4 42.7 2 Jan         424.6 357.5 high 119%
Geraldton Airport Comparison 27.2 +1.3 43.6 10 Feb 14.8 +1.2 3.0 26 Aug        
Kalbarri 29.0 +1.4 42.0 27 Dec 16.2 +1.7 3.8 5 Aug 415.8 352.5 high 118%
Morawa Airport 28.0 -0.1 44.8 27 Jan 13.8 +1.2 1.3 6 Jul 460.0 289.2 v high 159%
Mullewa 28.3 +0.4 44.0 1 Jan 14.9 +1.8 3.4 7 Jul 499.5 335.5 v high 149%
North Island 25.9 +1.4 35.7 14 Feb 19.6 +1.2 10.2 12 Aug 477.0
Wongan Hills 26.3 +0.7 42.5 28 Jan 12.8 +0.9 2.5 4 Jul 504.1 388.9 high 130%
Central Coast (district 09)
Badgingarra Research Stn 26.2 +0.4 42.9 27 Jan 13.3 +1.5 2.0 14 Oct
Bickley 23.2 +0.7 38.1 28 Jan 12.2 +1.1 3.0 5 Aug 1204.6 1079.9 high 112%
Champion Lakes 25.0   39.5 29 Jan 14.9   3.8 4 Jul
Garden Island HSF 23.9   37.9 28 Dec 15.9   7.4 4 Jul        
Gingin Aero 26.2 +0.8 41.2 29 Jan 12.8 +2.0 0.0 4 Jul 757.0 638.5 high 119%
Jandakot Aero 25.8 +1.4 40.6 29 Jan 12.9 +1.7 -0.4 4 Jul 915.6 831.6 average 110%
Jurien Bay 26.5 +1.7 42.0 28 Dec        
Karnet 23.4 +0.9 38.0 2 Jan     1.2 4 Jul 1188.4 1171.2 average 101%
Lancelin 26.0 +1.9 41.8 28 Dec        
Medina Research Centre 25.7 +1.5 40.0 16 Feb 14.0 +1.8 1.3 4 Jul 750.0 762.2 average 98%
Pearce RAAF 26.1 +1.0 41.8 28 Jan 13.8 +1.6 0.7 4 Jul 637.2 658.1 average 97%
Perth Airport 26.1 +1.7 41.8 29 Jan 13.6 +1.5 0.2 4 Jul 834.2 775.1 average 108%
Perth Metro 25.7 +1.2 40.4 29 Jan 14.0 +1.4 1.3 4 Jul 860.8 850.0 average 101%
Rottnest Island 23.2 +1.1 36.3 28 Dec 16.7 +1.1 9.2 3 Jul 712.4 682.7 average 104%
Swanbourne 25.5 +1.6 40.1 28 Dec 14.9 +1.1 4.7 4 Jul 822.6 725.7 high 113%
South Coast (district 09A)
Albany 20.4 +0.9 37.9 5 Jan 13.1 +1.4 1.8 18 Jul 966.3 931.4 average 104%
Albany Airport 20.8 +0.6 38.9 5 Jan 11.2 +0.7 0.4 18 Jul 955.8 798.0 high 120%
Bridgetown Comparison 23.8 +1.4 39.2 29 Dec 9.7 +1.7 -1.2 18 Jul 831.6 823.8 average 101%
Bunbury 24.0 +1.0 37.7 2 Jan 12.2 +1.3 1.0 28 Sep 757.6 726.9 average 104%
Busselton Aero 24.1 +1.2 37.7 29 Dec 11.3 +1.2 1.5 5 Aug 635.8 698.4 low 90%
Cape Leeuwin 21.2 +1.5 33.9 4 Dec 15.3 +1.2 6.7 6 Aug 869.6 969.1 low 90%
Cape Naturaliste 22.8 +2.2 35.4 16 Feb 14.0 +1.3 6.4 9 Jul 653.6 810.6 low 81%
Collie East 23.7   39.2 26 Feb 9.6   -1.9 18 Jul  
Donnybrook 24.6 +1.5 39.8 28 Jan 11.7 +2.0 0.6 5 Jul 1039.0 976.5 average 106%
Dwellingup 23.5 +1.7 38.1 29 Jan 11.0 +1.5 -0.6 4 Jul 1187.6 1244.4 average 95%
Esperance 22.6 +0.8 42.6 22 Jan 12.8 +0.8 5.1 10 Jul 656.4 616.6 average 106%
Esperance Aero 22.6 +0.6 44.6 28 Jan 11.8 +0.6 4.2 17 Jul 602.0 565.7 high 106%
Harvey 24.5 +0.9 39.0 28 Jan 11.8 +0.6 2.0 5 Jun 1048.5 854.4 high 123%
Hopetoun North 22.3 +0.1 41.7 22 Jan 12.3 +0.8 3.7 13 Jun 690.6 501.4 v high 138%
Jarrahwood 23.9 +1.5 39.5 25 Feb 9.5 +0.9 -2.6 18 Jul 876.6 928.0 average 94%
Mandurah 24.2   38.4 2 Jan 15.7   6.3 4 Jul        
Manjimup 22.0 +1.7 39.0 29 Dec 10.6 +1.0 1.7 5 Aug        
Pemberton 22.1 +1.8 38.2 29 Dec 11.7 +1.6 2.4 18 Jul
Rocky Gully 21.4 +0.6 38.2 29 Dec 10.4 +0.9 1.3 5 Aug        
Shannon 21.0 +0.6 38.2 29 Dec 10.4 +0.8 0.6 18 Jul        
Witchcliffe 22.4 +1.2 38.0 29 Dec 11.3 +0.8 1.1 6 Aug
North Central (district 10)
Cunderdin Airfield 26.2 +0.4 44.2 28 Jan 11.7 +1.4 -1.4 28 Sep
Northam 26.2 +0.9 43.9 28 Jan 11.8 +0.9 0.3 4 Jul 466.3 428.9 average 109%
York 25.8 +0.4 43.0 28 Jan 10.8 +1.4 -1.5 5 Aug 457.6 380.9 v high 120%
South Central (district 10A)
Beverley 25.9 +0.6 42.4 28 Jan 11.5 +1.3 0.2 4 Jul 520.1 419.5 high 124%
Brookton 24.7 +0.5 42.4 28 Jan         466.3 452.0 average 103%
Corrigin 24.4 +0.7 43.6 28 Jan 11.2 +1.3 -1.1 5 Aug 405.8 373.2 average 109%
Hyden 25.6 +0.6 45.5 28 Jan 11.5 +1.6 -2.0 26 Aug 472.4 340.2 v high 139%
Katanning 22.5 +0.1 43.5 28 Jan         668.4 453.9 v high 147%
Katanning Comparison 22.8 +0.7 41.8 28 Jan 10.2 +0.9 -1.5 18 Jul 660.3 479.2 v high 138%
Lake Grace 23.5 +0.1 44.4 28 Jan 11.2 +1.0 0.4 5 Aug 458.6 334.6 high 137%
Lake Grace Comparison                 444.6 351.1 high 127%
Narembeen                 469.7 332.4 v high 141%
Narrogin 23.1 +0.7 42.0 28 Jan 10.8 +1.4 -0.6 5 Aug 619.5 496.1 high 125%
Newdegate Research Station 23.5 +0.3 45.1 28 Jan 9.5 +0.8 -1.8 10 Sep 503.4 370.4 high 136%
Ongerup 22.2 +0.5 41.6 28 Jan 10.5 +0.8 1.4 5 Jun 491.0 386.0 high 127%
Pingelly 24.1 +0.8 42.1 28 Jan 11.4 +1.0 0.8 4 Jul 562.6 446.9 high 126%
Wagin 23.4 +0.5 42.2 28 Jan 10.5 +0.8 0.0 5 Aug 611.2 434.9 v high 141%
Wandering 23.9 +0.2 42.4 28 Jan 9.9 +1.6 -1.0 4 Jul 725.0 507.1 v high 143%
Eucla (district 11)
Balladonia 24.5 -0.1 45.9 29 Jan 11.2 +1.4 1.0 17 Jul 335.4 262.6 high 128%
Eucla 23.1 +0.3 47.1 29 Jan 13.1 +0.9 3.0 8 Aug 405.4 272.5 v high 149%
Eyre 23.4 +0.6 45.9 29 Jan 10.8 0.0 -4.1 24 Sep 603.8 310.5 v high 194%
Forrest 25.3 -0.9 48.4 30 Jan 11.4 +0.5 1.2 15 Jun
Red Rocks Point 22.2   45.3 29 Jan 13.7   3.4 2 Jul 544.8
South East (district 12)
Bulga Downs 28.0   43.5 23 Jan 13.7   -0.1 6 Aug 499.7 234.3 v high 213%
Kalgoorlie-Boulder Airport 24.8 -0.5 44.9 28 Jan 12.7 +1.0 0.4 6 Jul 390.0 264.5 high 147%
Laverton Aero 26.3 -0.5 45.8 28 Jan 14.0 +0.1 0.0 4 Jul        
Leinster Aero 27.5 -0.6 43.6 23 Jan                
Leonora 27.0 -0.9 46.2 28 Jan 14.3 +0.4 2.2 9 Jul 515.2 236.1 v high 218%
Leonora Aero 26.8   45.9 28 Jan 14.5   1.7 4 Jul 450.4
Munglinup West 23.2   45.3 28 Jan 11.0   2.8 17 Aug 534.6
Norseman Aero 24.9 -0.2 45.6 28 Jan 10.8 +1.0 -1.1 25 Aug 280.2 292.9 average 96%
Salmon Gums Res.Stn. 24.2 +0.8 46.3 28 Jan 9.9 +0.9 -3.4 11 Sep 372.2 353.6 average 105%
Southern Cross Airfield 25.5 -0.3 44.5 28 Jan 11.7 +1.6 -1.2 5 Aug 451.8 313.5 high 144%
North East (district 13)
Carnegie                 524.4 234.5 highest 224%
Giles Meteorological Office 28.9 -0.4 44.8 28 Jan 15.5 -0.4 0.9 13 Jun
Telfer Aero 33.0 -1.1 46.4 21 Dec 18.8 -0.6 2.1 14 Jun 634.0 366.8 v high 173%
Warburton Airfield 29.3 -0.5 46.5 28 Jan 14.8 +0.1 -0.3 15 Jun 515.2 246.0 v high 209%
Wiluna 29.0 -0.1 44.5 24 Dec 15.2 +0.9 1.1 15 Jun 426.2 256.5 v high 166%
Offshore Islands (district 200)
Christmas Island Aero 26.9 -0.4 29.9 27 Dec 22.8 0.0 19.0 11 Jul 2387.2 2099.3 average 114%
Cocos Island Airport 29.2 +0.2 31.6 22 Jan 24.9 +0.4 21.2 11 Oct 1857.2 1982.7 average 94%

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 11 am on Tuesday 3 January 2012. 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