Tuesday, 3 January 2012 - Monthly Climate Summary for Perth - Product code IDCKGC21L0
Perth in December 2011: A very wet December
- Rainfall: Wettest on record for several sites, 3rd wettest for Perth Metro
- Maximum temperature: Average to above average
- Minimum temperature: Average to above average; highest on record for a number of sites
Details Extremes Records Summaries Important notes the top
Rainfall
Rainfall across the Perth metropolitan area during December 2011 was well above average, with many sites experiencing their wettest December on record. Rainfall totals were generally in the 40 to 70 mm range, mainly as a result of two significant rainfall events in the first half of the month, which caused record December daily falls at several sites.
A deep middle level trough off the west coast produced significant rainfall and thunderstorms across the Perth metropolitan area on the 6th, and showers continued in the southeastern suburbs on the 7th. Rainfall totals during the event were generally in the 20 mm to 40 mm range, though heavier falls were recorded at Roleystone and Pearce RAAF. The daily rainfall total of 48.8 mm recorded at Pearce RAAF in the 24 hours to 9am on the 7th was its wettest December day in 48 years of record, as well as the wettest day of December 2011 in the Perth area.
Another deep mid-level trough off the WA west coast on the 12th brought heavy rain and thunderstorms across the Perth metropolitan area in the evening and early on the 13th, with several sites, including Perth Airport, experiencing their wettest December day on record. Most of the rain fell due to a slow moving storm in the hours just prior to midnight on the 12th, with Perth Metro recording 36.6 mm in 30 minutes (between 2202 WST and 2231 WST), which is a one in 50 to a one in 100 year event. The daily total of 43.6 mm at Perth Metro on the 13th was its third wettest December day since records commenced in 1876.
Perth Metro observed 75.8 mm on 3 rain days in December 2011, which was the third wettest December on record, and the wettest since 80.7 mm was recorded on 11 rain days in 1951. Last December, Perth Metro recorded 11.6 mm on 6 rain days.
Maximum temperature
Mean maximum temperatures were above average for most sites in the Perth metropolitan area, with temperatures mostly between 1.2 °C and 2.4 °C above average, though mean maxima at Pearce RAAF, Gosnells, and Bickley were close to average. Mean maximum temperatures were generally in the 28 °C to 31 °C range.
Several coastal plain sites experienced a heatwave (three or more consecutive days with maximum temperatures of 35 °C or higher) between the 3rd and 5th with temperatures in the 35 °C to 37 °C range, as a high pressure system moved slowly south of the state into the Bight directing dry and hot northeasterly winds over the Perth region. The temperature dipped sharply on the 6th due to a cool southerly change, with maximum temperatures in the low twenties and all sites observed their coolest day of the month. Bickley observed the coolest day across the Perth region with a maximum temperature of only 20.3 °C. Maximum temperatures warmed up towards the end of the month, with the hottest day on the 28th when daily maxima for all sites climbed above 36.0 °C. The 40.1 °C on the 28th at Swanbourne was the highest temperature recorded in the Perth metropolitan area for the month.
Perth Metro's mean daily maximum temperature in December 2011 was 30.5 °C, which was above the average of 28.8 °C for December. Daily maxima in December 2011 ranged from a mild 23.9 °C on the 13th, to a very hot 39.9 °C on the 28th. The first five days of December saw temperatures between 32 °C and 38 °C at Perth Metro, with a mean over this period of 35.4 °C. This was the warmest start to December at Perth Metro since records commenced in 1897, exceeding the previous warmest start to the month with a mean of 35.0 °C from 1 to 5 December 1967.
Minimum temperature
Mean minimum temperatures in December 2011 were very much above average across the Perth area, with a number of sites observing their warmest December on record due to consistently above average nights and some very warm nights in the early and latter parts of December. Mean overnight temperatures were generally in the 17 °C to 19 °C range.
Warm nights (when the daily minimum temperature is 20 °C or higher) were experienced at many sites between the 4th and 5th, and on the last four days of the month. The daily minimum temperature of 25.9 °C at Gosnells City on the 29th was the highest overnight temperature of the month in the Perth area.
Perth Metro's mean daily minimum temperature in December 2011 was 18.2 °C, which is 2.0 °C above the average and the warmest December for 32 years since a mean minimum of 18.5 °C was recorded in 1979. Daily minima ranged from a mild 13.3 °C on the 19th to a warm 23.2 °C on the 4th. Last December, Perth Metro recorded a mean minimum temperature of 16.6 °C.
Wind and Sunshine
The highest wind gust recorded in the Perth metropolitan area in December was 76 km/h at several locations during the two thunderstorm events in the first half of the month, and in blustery northeasterlies at Champion Lakes on the 4th.
Perth recorded an average daily sunshine of 10.2 hours per day in December 2011, which was well below the average of 11.6 hours, and the least sunniest December since 9.8 hours per day was recorded in 1983.
Further information
- Media
- media@bom.gov.au (03) 9669 4057
- Enquiries
- helpdesk.climate@bom.gov.au
| Extremes in December 2011 | |
|---|---|
| Hottest day | 40.1 °C at Swanbourne on the 28th |
| Warmest days on average | 30.9 °C at Gosnells
City 30.9 °C at Pearce RAAF |
| Coolest days on average | 26.5 °C at Rottnest
Island 27.9 °C at Bickley |
| Coldest day | 20.3 °C at Bickley on the 6th |
| Coldest night | 10.0 °C at Jandakot Aero on the 19th |
| Coolest nights on average | 15.2 °C at Bickley |
| Warmest nights on average | 19.0 °C at Rottnest
Island 18.3 °C at Swanbourne |
| Warmest night | 25.7 °C at Gosnells City on the 29th |
| Wettest overall | 75.8 mm at Perth Metro |
| Wettest day | 48.8 mm at Pearce RAAF on the 7th |
| Highest wind gust | 76 km/h at Champion
Lakes on the 4th 76 km/h at Rottnest Island on the 6th & 12th 76 km/h at Bickley on the 13th |
Details Extremes Records Summaries Important notes the top
| Record highest December daily rainfall | ||||||
|---|---|---|---|---|---|---|
| Highest daily rainfall in December 2011 (mm) |
Previous highest for December |
Years of record |
||||
| Perth Airport | 35.2 | on the 13th | 27.2 | on the 3rd in 1951 | 68 | |
| Pearce RAAF | 48.8 | on the 7th | 34.5 | on the 18th in 1952 | 57 | |
| Roleystone | 40.0 | on the 7th | 28.4 | on the 27th in 1966 | 44 | |
| Medina Research Centre | 26.8 | on the 13th | 25.2 | on the 31st in 1983 | 29 | |
| Swanbourne | 29.8 | on the 13th | 14.2 | on the 10th in 2008 | 19 | |
| Garden Island HSF | 19.4 | on the 7th | 7.4 | on the 21st in 2008 | 11 | |
| Record highest total December rainfall | |||||
|---|---|---|---|---|---|
| Total rainfall for December 2011 (mm) |
Previous highest for December |
Years of record |
Average for December |
||
| Perth Airport | 65.8 | 65.5 | in 1951 | 68 | 11.2 |
| Pearce RAAF | 65.0 | 53.6 | in 1952 | 49 | 10.2 |
| Roleystone | 67.2 | 44.4 | in 1967 | 44 | 15.2 |
| Bickley | 41.0 | 40.6 | in 1983 | 41 | 13.2 |
| Medina Research Centre | 51.8 | 29.4 | in 1983 | 29 | 10.6 |
| Swanbourne | 67.0 | 24.8 | in 2008 | 19 | 10.9 |
| Garden Island HSF | 38.8 | 13.6 | in 2005 | 11 | 9.7 |
| Record highest December mean daily minimum temperature | |||||
|---|---|---|---|---|---|
| Mean daily minimum temperature for December 2011 (°C) |
Previous highest for December |
Years of record |
Average for December |
||
| Pearce RAAF | 17.3 | 17.1 | in 2002 | 52 | 14.4 |
| Medina Research Centre | 17.7 | 16.6 | in 2002 | 24 | 14.9 |
| Jandakot Aero | 16.7 | 16.5 | in 1999 | 21 | 14.5 |
| Swanbourne | 18.3 | 17.8 | in 2002 | 18 | 16.4 |
| Bickley | 15.2 | 14.8 | in 1999 | 17 | 13.4 |
| Garden Island HSF | 18.8 | 18.0 | in 2002 | 10 | 16.9 |
Details Extremes Records Summaries Important notes the top
| Summary statistics for December 2011 | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Maximum temperatures for December (°C) |
Minimum temperatures for December (°C) |
Rainfall for December (millimetres) |
||||||||||
| Mean for December 2011 |
Diff from average |
Highest for December 2011 |
Mean for December 2011 |
Diff from average |
Lowest for December 2011 |
Total for December 2011 |
Average for December |
Rank of December 2011 |
Fraction of December average |
|||
| Bickley | 27.9 | 0.0 | 36.0 | 28th | 15.2 | +1.8 | 11.5 | 1st | 41.0 | 13.2 | highest | 311% |
| Champion Lakes | 29.5 | 37.9 | 28th | 18.2 | 14.3 | 19th | 65.8 | |||||
| Garden Island HSF | 27.6 | +2.4 | 37.9 | 28th | 18.8 | +1.9 | 15.9 | 1st | 38.8 | 9.7 | highest | 400% |
| Gosnells City | 30.9 | +0.7 | 39.6 | 28th | 55.4 | 11.5 | v high | 482% | ||||
| Jandakot Aero | 30.1 | +1.2 | 39.1 | 28th | 16.7 | +2.2 | 10.0 | 19th | 39.0 | 10.5 | v high | 371% |
| Medina Research Centre | 30.1 | +2.2 | 39.6 | 28th | 17.7 | +2.8 | 12.9 | 19th | 51.8 | 10.6 | highest | 489% |
| Pearce RAAF | 30.9 | +0.7 | 38.6 | 28th | 17.3 | +2.9 | 12.0 | 19th | 65.0 | 10.2 | highest | 637% |
| Perth Airport | 30.6 | +1.7 | 38.8 | 28th | 17.5 | +2.7 | 11.5 | 19th | 65.8 | 11.2 | highest | 588% |
| Perth Metro | 30.5 | +1.7 | 39.9 | 28th | 18.2 | +2.0 | 13.3 | 19th | 75.8 | 12.8 | 3rd highest | 592% |
| Rottnest Island | 26.5 | +1.6 | 36.3 | 28th | 19.0 | +1.5 | 16.6 | 7th | 70.0 | 8.2 |
2nd highest |
854% |
| Swanbourne | 29.9 | +2.2 | 40.1 | 28th | 18.3 | +1.9 | 15.8 | 10th | 67.0 | 10.9 | highest | 615% |
Details 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 | 29.5 | 31.0 | 32.8 | 31.4 | 32.9 | 20.3 | 22.9 | 23.0 | 23.3 | 27.4 | 29.1 | 23.5 | 20.4 | 24.8 | 21.2 | 25.8 | 27.9 | 24.3 | 23.9 | 29.3 | 30.6 | 30.5 | 28.0 | 28.9 | 28.6 | 28.6 | 33.2 | 36.0 | 35.0 | 31.8 | 28.5 |
| Champion Lakes | 31.3 | 33.0 | 34.7 | 32.3 | 33.8 | 22.6 | 25.9 | 25.1 | 26.9 | 29.6 | 32.1 | 24.3 | 22.5 | 27.2 | 23.7 | 28.0 | 28.8 | 24.9 | 25.1 | 30.3 | 29.8 | 30.8 | 29.4 | 30.9 | 30.4 | 31.0 | 34.7 | 37.9 | 35.8 | 30.9 | 29.9 |
| Garden Island HSF | 33.1 | 34.7 | 35.5 | 34.8 | 33.3 | 23.0 | 26.3 | 23.0 | 23.8 | 27.1 | 28.5 | 23.7 | 23.5 | 28.0 | 27.2 | 25.2 | 25.9 | 23.8 | 24.0 | 24.7 | 23.1 | 23.7 | 23.2 | 25.6 | 26.1 | 28.7 | 33.6 | 37.9 | 35.0 | 25.0 | 25.0 |
| Gosnells City | 32.8 | 35.5 | 37.0 | 35.8 | 23.8 | 27.4 | 26.9 | 27.4 | 31.4 | 33.2 | 26.3 | 24.9 | 28.5 | 25.0 | 25.5 | 30.5 | 26.9 | 26.8 | 31.7 | 32.9 | 31.0 | 32.5 | 32.5 | 36.9 | 39.6 | 38.5 | 33.0 | 31.0 | |||
| Jandakot Aero | 32.7 | 34.2 | 36.1 | 35.6 | 34.5 | 23.2 | 26.6 | 26.2 | 26.3 | 29.7 | 31.8 | 26.2 | 23.6 | 28.3 | 25.9 | 27.7 | 29.3 | 25.6 | 25.8 | 29.9 | 28.9 | 29.9 | 29.4 | 31.4 | 31.9 | 31.8 | 35.6 | 39.1 | 37.8 | 29.8 | 29.3 |
| Medina Research Centre | 33.2 | 34.9 | 36.9 | 36.1 | 35.9 | 23.8 | 27.4 | 25.9 | 25.9 | 29.4 | 32.0 | 26.7 | 23.7 | 29.4 | 26.5 | 27.4 | 28.9 | 25.3 | 25.7 | 29.5 | 27.9 | 28.3 | 27.5 | 30.4 | 29.2 | 32.5 | 35.4 | 39.6 | 37.9 | 30.7 | 30.1 |
| Pearce RAAF | 31.9 | 34.2 | 36.1 | 36.5 | 35.8 | 22.9 | 28.3 | 26.3 | 27.5 | 30.6 | 30.4 | 29.4 | 23.4 | 28.9 | 27.2 | 28.9 | 26.1 | 27.0 | 31.4 | 31.8 | 31.8 | 30.3 | 32.2 | 31.6 | 31.7 | 35.0 | 38.6 | 37.0 | 32.1 | 31.0 | |
| Perth Airport | 32.6 | 34.3 | 36.1 | 36.7 | 35.8 | 23.3 | 27.5 | 26.1 | 27.0 | 30.3 | 32.3 | 26.8 | 24.2 | 28.4 | 27.1 | 28.0 | 29.4 | 26.1 | 26.0 | 31.3 | 30.3 | 31.0 | 30.2 | 31.7 | 31.4 | 31.6 | 35.3 | 38.8 | 37.2 | 31.6 | 30.0 |
| Perth Metro | 32.9 | 34.9 | 36.4 | 37.6 | 35.1 | 24.2 | 27.6 | 26.8 | 26.8 | 30.1 | 31.7 | 26.3 | 23.9 | 29.1 | 26.5 | 28.1 | 29.6 | 25.5 | 26.3 | 30.6 | 29.2 | 30.4 | 28.5 | 30.9 | 30.2 | 32.1 | 36.1 | 39.9 | 37.8 | 30.8 | 29.6 |
| Rottnest Island | 30.0 | 33.2 | 33.7 | 32.9 | 31.9 | 21.4 | 24.5 | 23.4 | 23.5 | 24.4 | 27.4 | 23.5 | 22.6 | 25.1 | 25.6 | 24.0 | 26.0 | 23.8 | 23.1 | 24.7 | 24.0 | 24.6 | 23.6 | 24.7 | 24.1 | 25.5 | 29.8 | 36.3 | 32.3 | 25.6 | 25.3 |
| Swanbourne | 33.4 | 35.5 | 36.9 | 36.4 | 34.7 | 24.1 | 27.3 | 25.2 | 25.8 | 30.5 | 32.7 | 28.3 | 24.6 | 30.3 | 27.7 | 28.2 | 26.9 | 24.8 | 25.9 | 25.8 | 26.7 | 26.8 | 29.2 | 29.8 | 32.0 | 36.1 | 40.1 | 35.9 | 27.4 | 27.1 | |
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 |
Details 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 | 11.5 | 13.6 | 14.5 | 18.9 | 19.5 | 15.7 | 14.3 | 13.7 | 14.3 | 13.6 | 15.0 | 16.2 | 14.3 | 15.6 | 15.7 | 13.6 | 13.7 | 13.3 | 12.3 | 12.9 | 16.4 | 15.3 | 16.8 | 13.7 | 13.7 | 13.1 | 14.0 | 18.8 | 20.3 | 19.0 | 17.6 |
| Champion Lakes | 15.6 | 17.0 | 19.0 | 23.9 | 23.5 | 19.6 | 17.8 | 15.2 | 18.2 | 17.0 | 18.8 | 19.6 | 17.3 | 18.4 | 19.5 | 16.9 | 17.7 | 15.1 | 14.3 | 16.2 | 15.8 | 16.0 | 16.6 | 17.6 | 17.3 | 16.7 | 18.3 | 22.4 | 24.4 | 19.8 | 20.0 |
| Garden Island HSF | 15.9 | 17.4 | 19.4 | 21.1 | 22.7 | 19.6 | 18.5 | 18.6 | 18.0 | 16.5 | 19.0 | 19.6 | 17.6 | 19.1 | 19.3 | 16.6 | 16.9 | 19.4 | 16.1 | 16.5 | 19.6 | 19.4 | 19.4 | 17.3 | 17.5 | 16.8 | 18.5 | 21.6 | 21.5 | 22.2 | 19.8 |
| Gosnells City | 16.2 | 17.1 | 19.0 | 23.9 | 18.3 | 17.0 | 19.3 | 22.0 | 17.5 | 18.1 | 19.5 | 17.1 | 17.5 | 15.5 | 13.9 | 15.6 | 15.6 | 15.6 | 17.5 | 17.0 | 18.5 | 22.8 | 25.7 | 20.5 | 20.5 | ||||||
| Jandakot Aero | 15.2 | 16.9 | 18.9 | 22.3 | 22.5 | 19.3 | 17.2 | 15.3 | 17.4 | 14.5 | 16.6 | 18.7 | 16.3 | 17.6 | 18.8 | 15.2 | 12.6 | 14.1 | 10.0 | 14.2 | 13.6 | 15.4 | 16.4 | 16.9 | 16.8 | 16.2 | 15.2 | 21.4 | 17.8 | 18.1 | 17.7 |
| Medina Research Centre | 15.6 | 17.1 | 19.4 | 24.0 | 23.1 | 18.7 | 17.3 | 15.9 | 17.4 | 15.9 | 18.1 | 20.0 | 16.8 | 18.4 | 18.8 | 15.1 | 13.6 | 16.7 | 12.9 | 15.0 | 14.5 | 16.5 | 17.1 | 16.4 | 16.7 | 16.4 | 18.0 | 22.9 | 20.0 | 20.2 | 19.5 |
| Pearce RAAF | 16.6 | 14.8 | 19.8 | 25.2 | 23.8 | 18.1 | 17.6 | 15.5 | 17.5 | 15.9 | 18.8 | 17.4 | 17.1 | 18.1 | 19.7 | 16.5 | 13.5 | 12.6 | 12.0 | 13.3 | 14.0 | 14.9 | 16.7 | 16.2 | 17.5 | 16.8 | 18.7 | 20.8 | 20.6 | 18.1 | 19.7 |
| Perth Airport | 15.3 | 17.4 | 18.5 | 22.3 | 22.7 | 18.3 | 17.0 | 16.4 | 17.7 | 15.4 | 18.0 | 19.5 | 17.4 | 18.7 | 19.2 | 16.5 | 15.0 | 15.4 | 11.5 | 14.2 | 13.7 | 16.1 | 17.0 | 17.1 | 17.3 | 16.8 | 17.6 | 19.7 | 23.1 | 18.0 | 19.1 |
| Perth Metro | 15.4 | 17.6 | 19.2 | 23.2 | 21.5 | 19.1 | 17.9 | 17.2 | 18.1 | 16.6 | 18.5 | 19.4 | 16.9 | 18.6 | 19.4 | 16.7 | 16.4 | 17.0 | 13.3 | 16.6 | 17.4 | 17.0 | 17.8 | 17.6 | 17.5 | 16.8 | 18.0 | 21.8 | 21.3 | 21.3 | 20.3 |
| Rottnest Island | 16.8 | 17.9 | 19.7 | 22.7 | 21.9 | 18.9 | 16.6 | 18.5 | 17.9 | 17.2 | 19.7 | 19.8 | 16.8 | 19.1 | 19.3 | 16.6 | 18.0 | 18.7 | 17.8 | 17.1 | 19.1 | 19.1 | 19.1 | 18.0 | 17.9 | 17.5 | 18.9 | 22.0 | 23.7 | 21.4 | 20.9 |
| Swanbourne | 16.2 | 17.1 | 19.3 | 23.6 | 21.4 | 18.2 | 17.5 | 16.1 | 17.4 | 15.8 | 18.3 | 19.8 | 16.4 | 17.7 | 18.9 | 15.9 | 16.1 | 16.9 | 17.3 | 16.7 | 17.5 | 17.1 | 17.3 | 16.8 | 18.1 | 22.3 | 22.4 | 21.3 | 20.7 | ||
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 |
Details 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 | - | - | - | - | - | 5.6 | 15.6 | - | - | - | - | - | 18.8 | 0.8 | - | - | - | - | - | - | - | - | 0.2 | - | - | - | - | - | - | - | - |
| Champion Lakes | - | - | - | 0.4 | - | 1.8 | 18.8 | 11.0 | - | - | - | - | 33.8 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Garden Island HSF | - | - | - | - | - | 1.0 | 19.4 | - | - | - | - | - | 18.2 | - | 0.2 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Gosnells City | - | - | - | - | - | 14.4 | 18.6 | 4.6 | 0.1 | »» | »» | 0.1 | 17.0 | 0.6 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Jandakot Aero | - | - | - | 0.8 | - | 1.8 | 23.6 | - | - | - | - | 0.4 | 12.4 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Jarrahdale | - | - | - | - | - | - | 22.0 | 18.6 | - | - | - | - | 29.2 | 0.4 | - | - | 0.2 | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Medina Research Centre | - | - | - | - | - | 1.8 | 23.2 | - | - | - | - | - | 26.8 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Mundaring | 8.0 | 24.4 | 1.4 | 17.8 | 2.8 | ||||||||||||||||||||||||||
| Pearce RAAF | - | - | - | - | - | 15.0 | 48.8 | - | - | - | 0.8 | 0.4 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | ||||
| Perth Airport | - | - | - | - | - | 9.8 | 20.8 | - | - | - | - | - | 35.2 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Perth Metro | - | - | - | - | - | 6.4 | 25.8 | - | - | - | - | - | 43.6 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Roleystone | 0.4 | 0.2 | 5.2 | 40.0 | 0.2 | 21.0 | 0.2 | ||||||||||||||||||||||||
| Rottnest Island | - | - | - | - | - | 2.2 | 31.4 | - | - | - | - | - | 36.2 | - | - | - | - | - | - | - | 0.2 | - | - | - | - | - | - | - | - | - | - |
| Serpentine | - | - | - | - | - | 0.8 | 18.2 | 8.0 | 0.2 | - | - | - | 36.8 | 0.2 | - | 0.4 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Swanbourne | - | - | - | - | 0.4 | 10.2 | 26.6 | - | - | - | - | - | 29.8 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | |||
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.
Details 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 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, 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
- Media
- media@bom.gov.au (03) 9669 4057
- Enquiries
- helpdesk.climate@bom.gov.au
Unless otherwise noted, all maps, graphs and diagrams in this page are licensed under the Creative Commons Attribution 4.0 International Licence
