Tuesday, 31 January 2012 - Monthly Climate Summary for Perth - Product code IDCKGC21L0
Perth in January 2012: A very hot January
This statement was prepared before all data for the period were available. This may affect some of the statistics presented.
- Rainfall: Mostly average to above average
- Maximum temperature: Above average for most sites
- Minimum temperature: Highest on record for most sites
Details Extremes Records Summaries Important notes the top
Rainfall
Rainfall across the Perth metropolitan area during January 2012 ranged from near average in western suburbs to above average in southern and eastern suburbs. Rainfall totals varied from less than 5 mm in coastal suburbs and on Rottnest Island to above 80 mm in the hills. The higher totals were mainly the result of one significant thunderstorm event in the second half of the month, which caused record January daily falls at several sites.
Overnight thunderstorms on the 3rd produced generally light rainfall across the Perth metropolitan area, with daily falls of less than 10 mm registered on the 4th. This was the first rainfall in Perth for three weeks since 13 December 2011. Further light showers occurred in the eastern suburbs and hills in the evening of the 5th and in the morning of the 6th, with daily totals less than 5 mm. After a length dry period, a surface trough off the west coast produced slow moving thunderstorms with significant rainfall across the Perth metropolitan area in the evening of the 19th and in the morning of the 20th. Rainfall totals during the event were generally in the 10 mm to 70 mm range. As a result, Jarrahdale, Mundaring and Chidlow registered their wettest January day in more than 100 years of rainfall record. Serpentine also witnessed its highest daily rainfall for January, and as a result of this single event recorded its wettest January in 86 years of record. Thunderstorms brought rain to most sites in the Perth metropolitan area on the afternoon and evening of Australia day, the 26th, though falls were generally less than 5 mm.
Perth Metro observed 18.8 mm on 5 rain days in January 2012, which was well above the long-term average of 9.6 mm. Last January, Perth Metro recorded 30.2 mm on 6 rain days.
Across December 2011 and January 2012, Perth Metro recorded 94.6 mm on 8 rain days, which is the 4th wettest December to January period since records commenced in 1876, and the wettest start to summer in 12 years, since 146.2 mm was recorded on 13 rain days in December 1999 and January 2000.
Maximum temperature
Although mean maxima at Pearce RAAF in the north and Bickley in the hills were close to average, most sites in the Perth metropolitan area saw above to very much above average mean maxima, in the range of 1.1 °C to 3.5 °C above normal. Swanbourne recorded its hottest January in 18 years of recording, whilst Garden Island also saw a record, though with only 10 years of recording history.
Cooler than normal days were experienced on the first day of January 2012, and between the 5th and the 8th, with daily maxima mostly in the mid-to-high twenties. In contrast, from the 10th of the month, a number of hot spells were experienced. The first heatwave (three or more consecutive days with maximum temperatures of 35 °C or higher) was mostly confined to the southeast and western suburbs between the 11th and 13th, whilst a second 4-day heatwave was witnessed at Perth Metro, Perth Airport, and Jandakot Aerodrome between the 18th and the 21st. Most sites in the Perth area experienced a very hot spell during the period between the 24th and the 28th, with daily maxima in the 35 to 43 °C range. The hottest day of the month was Australia day (26th) for most sites, though the 25th or 28th was hotter for some metropolitan locations, and the 43.1 °C on the 26th at Swanbourne was the highest temperature recorded in the Perth metropolitan area for the month, and also the highest temperature recorded at Swanbourne in 19 years of record. Cooler air from the southeast with maxima mostly in the low thirties brought some relief in the last days of the month after some sites recorded a six day heatwave.
Perth Metro's mean daily maximum temperature in January 2012 was 33.5 °C, which was 2.6 °C above the January average and the second hottest January on record, only behind the mean maximum of 34.4 °C recorded in January 1962. Daily maxima in January 2012 ranged from a mild 24.6 °C on the 7th, to a very hot 42.1 °C on the 28th.
Minimum temperature
Mean minimum temperatures in January 2012 were very much above average across the Perth region. Most sites observed their warmest January on record due to a large number of warm to very warm nights in the middle and latter parts of the month. Perth Airport recorded its warmest January in 67 years of record, whilst Rottnest Island recorded its 2nd warmest January from records going back to 1880, and its warmest January since the record was set in 1934. Mean overnight temperatures were generally in the 19 °C to 21 °C range across the city.
Warm nights (when the daily minimum temperature is 20 °C or higher) were experienced at many sites between the 13th and 14th, 19th and 22nd, and 24th and 29th. The hottest night of the month was the 28th with daily minima mostly in the 26 °C to 28 °C range as a number of sites recorded their hottest January night on record, and Gosnells City recorded the highest minimum for the month in Perth with 29.0 °C. The minimum temperature of 26.4 °C at Rottnest Island is the third highest minimum temperature recorded on the island since daily records commenced 1965.
Perth Metro's mean daily minimum temperature in January 2012 was 20.1 °C, which is 2.2°C above the average, and the warmest January for 20 years since a mean minimum of 20.6 °C was recorded in 1992. Daily minima ranged from a mild 13.5 °C on the 8th to a very warm 26.6 °C on the 28th. Last January, Perth Metro recorded a mean minimum temperature of 19.5 °C.
Wind and Sunshine
The highest wind gust recorded in the Perth metropolitan area in January was 98 km/h at Bickley on the 30th.
Perth recorded an average daily sunshine of 11.3 hours per day in January 2012, which is slightly below the average of 11.6 hours.
Further information
Western Australia Climate Services CentreBureau of Meteorology
Phone (08) 9263 2222
Email climate.wa@bom.gov.au
| Extremes in January 2012 | |
|---|---|
| Hottest day | 43.1 °C at Swanbourne on the 26th |
| Warmest days on average | 34.2 °C at Gosnells City |
| Coolest days on average | 29.6 °C at Rottnest
Island 30.5 °C at Bickley |
| Coldest day | 22.0 °C at Garden
Island HSF on the 7th 22.3 °C at Bickley on the 6th |
| Coldest night | 9.8 °C at Jandakot Aero on the 8th |
| Coolest nights on average | 16.9 °C at Bickley |
| Warmest nights on average |
20.8 °C at Rottnest Island 20.6 °C at Gosnells City |
| Warmest night | 29.0 °C at Gosnells City on the 28th |
| Warmest on average overall | 27.5 °C at Gosnells City |
| Coolest on average overall | 23.7 °C at Bickley |
| Wettest overall | 100.2 mm at Chidlow |
| Wettest day | 86.4 mm at Chidlow on the 20th |
| Highest wind gust | 98 km/h at Bickley on the 30th |
Extremes Records Summaries Important notes the top
| Record highest January daily rainfall | ||||||
|---|---|---|---|---|---|---|
| Highest daily rainfall in January 2012 (mm) |
Previous wettest for January |
Years of record |
||||
| Jarrahdale | 60.6 | on the 20th | 58.2 | on the 21st in 1982 | 105 | |
| Mundaring | 68.8 | on the 20th | 36.8 | on the 20th in 1923 | 104 | |
| Chidlow | 86.4 | on the 20th | 64.3 | on the 21st in 1957 | 104 | |
| Serpentine | 60.6 | on the 20th | 27.9 | on the 1st in 1960 | 86 | |
| Record highest total January rainfall | |||||
|---|---|---|---|---|---|
|
Total rainfall for January 2012 (mm) |
Previous wettest for January |
Years of record |
Average for January |
||
| Serpentine | 60.6 | 44.9 | in 1960 | 89 | 9.6 |
| Record highest January temperature | ||||||
|---|---|---|---|---|---|---|
|
Highest temperature in January 2012 (°C) |
Previous warmest for January |
Years of record |
Average for January |
|||
| Swanbourne | 43.1 | on the 26th | 42.9 | on the 17th in 2010 | 19 | 29.5 |
| Record highest January mean daily maximum temperature | |||||
|---|---|---|---|---|---|
| Mean daily maximum temperature for January 2012 (°C) |
Previous warmest for January |
Years of record |
Average for January |
||
| Swanbourne | 33.0 | 32.0 | in 2010 | 18 | 29.5 |
| Garden Island HSF | 30.4 | 28.9 | in 2010 | 10 | 27.0 |
| Record highest January daily minimum temperature | ||||||
|---|---|---|---|---|---|---|
| Highest daily minimum temperature in January 2012 (°C) |
Previous warmest for January |
Years of record |
Average for January |
|||
| Jandakot Aero | 27.3 | on the 28th | 27.1 | on the 19th in 2010 | 22 | 16.6 |
| Gosnells City | 29.0 | on the 28th | 28.6 | on the 19th in 2010 | 19 | 18.4 |
| Swanbourne | 28.0 | on the 28th | 26.5 | on the 7th in 1998 | 19 | 18.0 |
| Garden Island HSF | 25.9 | on the 28th | 24.4 | on the 19th in 2010 | 11 | 18.7 |
| Record highest January mean daily minimum temperature | |||||
|---|---|---|---|---|---|
| Mean daily minimum temperature for January 2012 (°C) |
Previous warmest for January |
Years of record |
Average for January |
||
| Perth Airport | 19.7 | 19.5 | in 1962 | 67 | 17.0 |
| Pearce RAAF | 20.0 | 19.8 | in 1989 | 50 | 16.9 |
| Medina Research Centre | 19.8 | 18.8 | in 2011 | 23 | 16.8 |
| Jandakot Aero | 19.4 | 18.8 | in 1992 | 21 | 16.6 |
| Bickley | 16.9 | 16.8 | in 2011 | 18 | 15.2 |
| Gosnells City | 20.6 | 20.5 | in 2011 | 18 | 18.4 |
| Swanbourne | 20.4 | 19.3 | in 2011 | 18 | 18.0 |
| Garden Island HSF | 20.4 | 19.9 | in 2011 | 10 | 18.7 |
Extremes Records Summaries Important notes the top
| Summary statistics for January 2012 | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Maximum temperatures for January (°C) |
Minimum temperatures for January (°C) |
Rainfall for January (millimetres) |
||||||||||
| Mean for January 2012 |
Diff from average |
Highest for January 2012 |
Mean for January 2012 |
Diff from average |
Lowest for January 2012 |
Total for January 2012 |
Average for January |
Rank of January 2012 |
Fraction of January average |
|||
| Bickley | 30.5 | -0.1 | 38.0 | 26th | 16.9 | +1.7 | 10.6 | 8th | 52.8 | 18.1 | v high | 292% |
| Champion Lakes | 32.5 | 40.6 | 28th | 20.3 | 12.1 | 8th | 21.6 | |||||
| Garden Island HSF | 30.4 | +3.4 | 40.2 | 25th | 20.4 | +1.7 | 15.0 | 8th | 24.6 | 11.6 | high | 212% |
| Gosnells City | 34.2 | +1.1 | 42.5 | 28th | 20.7 | +2.3 | 11.0 | 8th | 14.8 | 12.0 | high | 123% |
| Jandakot Aero | 33.4 | +2.2 | 41.5 | 26th | 19.4 | +2.8 | 9.8 | 8th | 12.8 | 14.6 | high | 88% |
| Medina Research Centre | 33.1 | +2.6 | 41.8 | 26th | 19.8 | +3.0 | 10.6 | 8th | 35.2 | 12.2 | high | 289% |
| Pearce RAAF | 33.9 | +0.4 | 41.3 | 26th | 19.8 | +2.9 | 10.9 | 8th | ||||
| Perth Airport | 33.4 | +1.7 | 41.5 | 26th | 19.7 | +2.7 | 11.9 | 8th | 27.2 | 9.7 | v high | 280% |
| Perth Metro | 33.5 | +2.6 | 42.1 | 28th | 20.1 | +2.2 | 13.5 | 8th | 18.8 | 9.6 | high | 196% |
| Rottnest Island | 29.6 | +3.3 | 39.5 | 25th | 20.8 | +1.8 | 16.1 | 8th | 1.0 | 7.8 | average | 13% |
| Swanbourne | 33.0 | +3.5 | 43.1 | 26th | 20.4 | +2.4 | 13.1 | 8th | 1.8 | 16.1 | average | 11% |
Extremes Records Summaries Important notes the top
| Daily maximum temperature | |||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Central Coast (09) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 |
| Bickley | 24.2 | 28.7 | 29.5 | 30.4 | 25.3 | 22.3 | 22.5 | 26.0 | 29.5 | 30.6 | 32.4 | 33.4 | 31.8 | 28.5 | 30.6 | 26.2 | 29.3 | 33.9 | 33.9 | 32.3 | 33.0 | 29.2 | 32.1 | 34.7 | 36.7 | 38.0 | 34.8 | 37.1 | 29.2 | 28.2 | |
| Champion Lakes | 26.3 | 30.4 | 31.4 | 32.8 | 26.9 | 24.1 | 24.0 | 27.5 | 31.4 | 32.9 | 34.4 | 34.9 | 33.7 | 32.1 | 31.6 | 26.6 | 31.4 | 36.4 | 35.4 | 35.3 | 33.8 | 29.2 | 34.9 | 37.3 | 39.2 | 40.4 | 37.7 | 40.6 | 31.3 | 30.6 | |
| Garden Island HSF | 24.8 | 24.1 | 32.0 | 33.6 | 27.4 | 24.3 | 22.0 | 23.8 | 25.5 | 30.2 | 34.9 | 36.4 | 31.8 | 29.3 | 23.1 | 26.4 | 31.2 | 30.9 | 35.9 | 32.3 | 25.1 | 29.0 | 37.1 | 40.2 | 37.7 | 37.0 | 32.2 | 31.8 | 31.6 | ||
| Gosnells City | 27.3 | 31.5 | 33.2 | 34.6 | 29.0 | 25.8 | 25.5 | 29.2 | 33.5 | 34.5 | 36.2 | 36.9 | 35.2 | 33.5 | 33.5 | 28.0 | 33.0 | 38.4 | 36.7 | 37.0 | 30.5 | 35.5 | 39.3 | 41.5 | 42.2 | 39.5 | 42.5 | 32.9 | |||
| Jandakot Aero | 26.8 | 31.3 | 33.0 | 34.4 | 28.2 | 25.1 | 24.5 | 27.0 | 32.1 | 34.3 | 35.6 | 36.9 | 35.4 | 33.0 | 32.8 | 27.3 | 31.2 | 37.6 | 35.0 | 36.5 | 35.4 | 28.7 | 34.5 | 38.3 | 40.9 | 41.5 | 39.4 | 41.4 | 33.0 | 31.7 | |
| Medina Research Centre | 27.5 | 29.5 | 32.4 | 33.9 | 29.0 | 25.0 | 24.0 | 26.1 | 29.2 | 34.0 | 36.0 | 37.0 | 36.0 | 35.2 | 32.8 | 25.8 | 29.0 | 37.2 | 34.9 | 36.0 | 35.4 | 26.6 | 34.0 | 38.0 | 41.2 | 41.8 | 39.7 | 41.3 | 32.4 | 31.5 | |
| Pearce RAAF | 28.8 | 32.7 | 33.1 | 35.7 | 31.3 | 26.4 | 25.7 | 29.1 | 32.8 | 34.4 | 35.5 | 36.2 | 34.5 | 31.8 | 34.2 | 28.5 | 32.6 | 36.6 | 35.3 | 37.3 | 32.4 | 35.8 | 39.6 | 40.4 | 41.3 | 35.0 | 40.8 | 33.3 | 32.2 | ||
| Perth Airport | 27.4 | 31.6 | 32.6 | 34.4 | 28.5 | 25.4 | 24.9 | 27.5 | 32.7 | 33.6 | 35.5 | 36.1 | 34.7 | 32.4 | 33.0 | 28.0 | 32.2 | 36.9 | 35.5 | 36.3 | 35.5 | 29.1 | 35.2 | 38.0 | 40.0 | 41.5 | 37.5 | 41.0 | 32.2 | 31.3 | |
| Perth Metro | 27.7 | 30.3 | 33.0 | 35.0 | 27.8 | 25.1 | 24.6 | 27.2 | 30.5 | 34.3 | 35.9 | 36.8 | 34.9 | 33.6 | 33.0 | 26.6 | 31.3 | 37.5 | 35.0 | 37.1 | 35.3 | 28.8 | 34.7 | 38.7 | 41.1 | 41.9 | 37.1 | 42.1 | 33.1 | 31.9 | |
| Rottnest Island | 24.9 | 24.2 | 29.9 | 32.7 | 26.1 | 24.2 | 23.2 | 22.1 | 24.7 | 28.3 | 32.7 | 29.8 | 34.3 | 33.2 | 28.9 | 24.1 | 24.8 | 30.2 | 30.3 | 35.9 | 30.4 | 26.2 | 27.4 | 31.3 | 39.5 | 36.6 | 36.1 | 35.5 | 29.4 | 30.2 | |
| Swanbourne | 27.7 | 27.2 | 33.6 | 35.6 | 27.0 | 25.0 | 24.4 | 26.1 | 30.0 | 34.1 | 36.9 | 37.3 | 35.3 | 33.7 | 30.8 | 25.8 | 30.0 | 37.7 | 31.3 | 38.2 | 32.5 | 27.9 | 33.5 | 39.4 | 41.8 | 43.1 | 37.0 | 38.9 | 34.0 | 32.7 | |
This table is very wide; you may have to scroll sideways to see all the days, and you may need to set the paper to 'landscape' to print.
| The temperatures in this table are coloured by their difference from the long-term average for the period |
-10.0 | -9.0 | -8.0 | -7.0 | -6.0 | -5.0 | -4.0 | -3.0 | -2.0 | -1.0 | 0.0 | +1.0 | +2.0 | +3.0 | +4.0 | +5.0 | +6.0 | +7.0 | +8.0 | +9.0 | +10.0 | °C difference from average |
Extremes Records Summaries Important notes the top
| Daily minimum temperature | |||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Central Coast (09) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 |
| Bickley | 16.6 | 14.8 | 14.4 | 13.0 | 17.5 | 16.3 | 12.9 | 10.6 | 12.8 | 13.6 | 15.6 | 17.9 | 19.6 | 21.1 | 19.0 | 14.4 | 12.8 | 14.9 | 19.0 | 17.7 | 18.3 | 20.5 | 17.8 | 17.0 | 20.6 | 20.9 | 23.7 | 24.0 | 18.8 | 13.0 | 13.5 |
| Champion Lakes | 19.8 | 18.5 | 18.1 | 16.5 | 20.9 | 19.8 | 16.4 | 12.1 | 16.6 | 17.6 | 19.8 | 21.8 | 23.7 | 24.9 | 22.5 | 17.1 | 16.3 | 19.2 | 22.4 | 20.1 | 20.9 | 23.0 | 18.8 | 20.7 | 24.2 | 25.5 | 26.1 | 28.3 | 22.5 | 17.0 | 17.7 |
| Garden Island HSF | 20.5 | 18.0 | 18.0 | 17.0 | 21.0 | 20.3 | 18.1 | 15.0 | 16.7 | 17.6 | 20.4 | 20.6 | 23.9 | 22.3 | 19.9 | 16.6 | 19.3 | 21.3 | 20.2 | 22.4 | 22.7 | 21.0 | 21.0 | 25.4 | 25.3 | 23.3 | 25.9 | 21.9 | 16.9 | 18.2 | |
| Gosnells City | 22.0 | 18.5 | 18.0 | 20.6 | 20.0 | 18.5 | 11.0 | 16.5 | 17.5 | 19.5 | 21.9 | 23.8 | 25.0 | 23.0 | 16.9 | 16.8 | 19.4 | 21.8 | 20.9 | 22.0 | 18.7 | 21.1 | 25.1 | 26.0 | 26.0 | 29.0 | 22.5 | 16.8 | |||
| Jandakot Aero | 19.0 | 17.7 | 17.5 | 17.6 | 18.0 | 19.8 | 14.6 | 9.8 | 16.1 | 17.2 | 19.7 | 19.3 | 23.7 | 24.5 | 19.4 | 17.0 | 15.2 | 17.0 | 19.4 | 21.1 | 20.5 | 22.4 | 18.5 | 20.4 | 25.1 | 24.3 | 23.8 | 27.3 | 21.4 | 16.3 | 17.3 |
| Medina Research Centre | 19.4 | 17.5 | 17.6 | 16.1 | 19.5 | 20.6 | 16.7 | 10.6 | 16.0 | 17.3 | 19.6 | 20.3 | 23.7 | 25.0 | 21.4 | 18.0 | 15.5 | 18.0 | 20.2 | 19.0 | 22.0 | 22.8 | 19.3 | 20.8 | 25.2 | 25.0 | 24.5 | 26.3 | 21.8 | 16.5 | 17.7 |
| Pearce RAAF | 18.2 | 18.1 | 18.0 | 18.9 | 18.2 | 19.8 | 14.2 | 10.9 | 16.0 | 17.2 | 20.5 | 22.1 | 23.4 | 23.9 | 22.8 | 16.7 | 15.2 | 19.4 | 17.3 | 21.3 | 23.1 | 22.9 | 17.0 | 20.7 | 26.7 | 25.1 | 27.9 | 22.3 | 16.8 | 18.8 | |
| Perth Airport | 19.7 | 18.0 | 18.2 | 16.2 | 18.6 | 20.7 | 14.7 | 11.9 | 16.4 | 17.1 | 19.3 | 19.8 | 23.4 | 24.4 | 21.8 | 17.6 | 16.5 | 18.7 | 20.1 | 19.4 | 18.9 | 23.0 | 19.1 | 20.7 | 24.6 | 25.0 | 23.7 | 26.2 | 22.1 | 16.6 | 17.5 |
| Perth Metro | 20.0 | 18.1 | 18.2 | 16.3 | 19.8 | 20.7 | 17.4 | 13.5 | 16.5 | 17.2 | 19.5 | 19.4 | 23.8 | 24.3 | 21.6 | 18.6 | 16.6 | 19.0 | 19.2 | 22.0 | 20.0 | 23.4 | 19.7 | 21.1 | 25.6 | 25.4 | 23.7 | 26.6 | 22.4 | 16.6 | 17.6 |
| Rottnest Island | 20.4 | 18.4 | 18.2 | 17.6 | 20.6 | 19.7 | 18.3 | 16.1 | 17.2 | 18.1 | 20.6 | 22.1 | 23.7 | 24.1 | 22.7 | 19.7 | 17.2 | 20.2 | 22.5 | 21.9 | 22.9 | 21.9 | 20.7 | 21.0 | 23.7 | 25.8 | 24.8 | 26.4 | 22.1 | 16.9 | 18.6 |
| Swanbourne | 19.4 | 17.8 | 17.6 | 18.1 | 19.9 | 19.9 | 17.5 | 13.1 | 16.7 | 17.7 | 19.9 | 19.9 | 24.1 | 24.0 | 22.1 | 18.2 | 15.9 | 19.2 | 20.8 | 22.5 | 23.1 | 22.2 | 19.8 | 20.8 | 25.2 | 26.6 | 25.0 | 28.0 | 21.6 | 16.4 | 18.1 |
This table is very wide; you may have to scroll sideways to see all the days, and you may need to set the paper to 'landscape' to print.
| The temperatures in this table are coloured by their difference from the long-term average for the period |
-10.0 | -9.0 | -8.0 | -7.0 | -6.0 | -5.0 | -4.0 | -3.0 | -2.0 | -1.0 | 0.0 | +1.0 | +2.0 | +3.0 | +4.0 | +5.0 | +6.0 | +7.0 | +8.0 | +9.0 | +10.0 | °C difference from average |
Extremes Records Summaries Important notes the top
| Daily rainfall | |||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Central Coast (09) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 |
| Bickley | - | - | - | 10.2 | - | 3.2 | 0.2 | - | - | - | - | - | - | - | - | - | - | - | - | 36.8 | 2.2 | - | - | - | - | - | 0.2 | - | - | - | - |
| Champion Lakes | - | - | - | 1.2 | 0.2 | 1.0 | 0.4 | - | - | - | - | - | - | - | - | - | - | - | - | 13.6 | 3.4 | - | - | - | - | - | 1.8 | - | - | - | - |
| Garden Island HSF | - | - | - | 3.6 | 0.2 | - | - | - | - | - | - | - | - | - | - | - | - | - | 18.4 | 2.4 | - | - | - | - | - | - | - | - | - | - | |
| Gosnells City | - | - | - | 3.0 | - | 0.8 | - | - | - | - | - | - | - | - | - | - | - | - | - | 4.8 | 0.2 | - | - | - | - | - | 6.0 | - | - | - | |
| Jandakot Aero | - | - | - | - | - | 0.4 | 0.4 | - | - | - | - | - | - | - | - | - | - | - | - | 10.4 | 1.6 | - | - | - | - | - | - | - | - | - | - |
| Jarrahdale | - | - | - | 0.8 | - | 2.4 | - | - | - | - | - | - | - | - | - | - | - | - | - | 60.6 | - | - | - | - | - | - | - | - | - | - | - |
| Medina Research Centre | - | - | - | 4.6 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 29.6 | 1.0 | - | - | - | - | - | - | - | - | - | - |
| Mundaring | 1.0 | 1.2 | 0.6 | 68.8 | 13.0 | 2.2 | |||||||||||||||||||||||||
| Pearce RAAF | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0.2 | - | 2.2 | - | - | - | - | ||||||
| Perth Airport | - | - | - | 2.2 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 14.2 | 6.0 | - | - | - | - | - | 4.8 | - | - | - | - |
| Perth Metro | - | - | - | 4.8 | - | - | 0.6 | - | - | - | - | - | - | - | - | - | - | - | - | 0.6 | 9.8 | - | - | - | - | - | 3.0 | - | - | - | - |
| Roleystone | 30.6 | ||||||||||||||||||||||||||||||
| Rottnest Island | - | - | - | 1.0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Serpentine | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 60.6 | - | - | - | - | - | - | - | - | - | - | - |
| Swanbourne | - | - | - | - | - | - | 0.2 | - | - | - | - | - | - | - | - | - | - | - | - | 0.2 | - | - | - | - | - | - | 1.4 | - | - | - | - |
Most values are the precipitation in the 24 hours to 9 am on the day indicated.
Days marked with »» are part of a longer accumulation, which is marked like this on the final day.
Values over 100 mm have been rounded to the nearest whole millimetre.
Days marked with - have a rainfall report of zero;
days left blank have no rainfall report (which often indicates no rain fell).
This table is very wide; you may have to scroll sideways to see all the days, and you may need to set the paper to 'landscape' to print.
Extremes Records Summaries Important notes the top
Notes
A Monthly Climate Summary is prepared to list the main features of the weather in Perth 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 9 am on Tuesday 31 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, 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.
Records in this summary are based on sites with at least 10 years of data.
*Official Perth observations have been recorded at several different sites with varying instrumentation over the years, and these changes can affect the continuity of the climate record. For the current Mt Lawley site, the most significant changes of this kind relate to minimum temperature and rain days.
For that reason, current mean temperature and rain-day data quoted here are based only on readings from the Mt Lawley site, which commenced observations in 1993. Sunshine recordings are from Perth Airport and for similar reasons current means use only Perth Airport data, which commenced in 1993.
For PDF files of Perth Metro climate statistics for other months, please click here for extremes and here for averages.
Further information
Western Australia Climate Services CentreBureau of Meteorology
Phone (08) 9263 2222
Email climate.wa@bom.gov.au
