Perth in February 2011: Very hot February in Perth

  • Rainfall: Below average.
  • Maximum temperature: Very much above average.
  • Minimum temperature: Very much above average, highest on record at a number of sites.

Rainfall

Rainfall during February 2011 in the Perth area was generally below average, with several sites observing no rainfall for the month; however, this is not uncommon for February. Measurable rainfall was confined to the 24 hours to 9am on 1 February 2011 for most sites, with totals generally less than 1 mm across the Perth Metropolitan area.

Severe thunderstorms developed during the afternoon of the 28th and produced heavy rainfall in northern, eastern and southern parts of the Perth Metropolitan area during the afternoon. Rainfall totals in the 24 hours to 9am on 1 March 2011 (which was likely to have fallen in the afternoon of 28 February) were 19.2 mm at Champion Lakes, 19.0 mm at Gosnells City, 9.6 mm at Jarrahdale, 4.2 mm at Bickley and 0.4 mm at Serpentine. Hourly data at Champion Lakes and Bickley indicate that Champion Lakes observed 19.2 mm between 1628 and 1800 WST on the 28 February, while Bickley observed 4.2 mm between 1556 and 1800 WST.

Perth Metro recorded 0.4 mm of rainfall on 1 rain day in February 2011. The average for February is 12.7 mm on 2.2 rain days. Historically, February rainfall at Perth Metro has ranged from nil on 17 occasions to 166.3 mm in 1955. Last February (2010), Perth Metro recorded 0.2 mm on 1 rain day.

Maximum temperature

Mean daily maximum temperatures across Perth in February 2011 were very much above average, with temperatures at all sites at least 2 °C above average. Jandakot, Swanbourne and Gosnells City broke their highest mean daily maximum records for February, and were more than 3 °C above average. Rottnest Island observed it's 3rd hottest February since records commenced on the island in 1880.

Very hot conditions were experienced in the latter part of February due to a broad surface trough over much of WA and another trough off the west coast dragging hot and humid northeasterly winds over Perth. Heatwave conditions were observed at most Perth stations during this time, with daily maximum temperatures generally in excess of 35 °C from the 21st through to the 28th, with little to no relief provided by the sea breeze. The hottest day for the month was observed during this period, with Pearce RAAF recording 40.9 °C on the 27th.

Perth Metro during February 2011 ranked 3rd highest in terms of mean daily maximum temperature, with a mean maximum temperature of 34.2°C for the month, which is this hottest February for 15 years since the 34.6 °C in 1996, but below the record of 35.1 °C set in 1985. The average for February is 31.3 °C. Daily maxima during February 2010 ranged from warm 29.6 °C on the 5th to very hot 39.0 °C on the 16th and 28th.

Daily maximum temperatures above 30 °C were recorded almost every day in February at sites on the Perth coastal plain, apart from the 1st and 5th which were in the very high 20s. Perth Metro recorded 23 consecutive days with a maximum temperature of 30 °C or greater during February 2011 (from the 6th to the 28th), which is the longest hot spell of this kind since the record of 25 days at Perth Metro was set from 29 January 1988 to 22 February 1988. With maximum temperatures forecast to be well into the 30's for the coming week, this record could well be broken in early March.

The Perth Metro site recorded its lowest maximum temperature for February of 29.6 °C on the 5th. This is the highest value of the lowest maximum for February since records commenced in 1897. The previous highest value for the lowest maximum temperature in February was 26.9 °C in 1985.

Minimum temperature

Very much above average temperatures also were reflected in the February minima with mean daily minimum temperature records broken at many sites across Perth during February 2011. All sites were least 2 °C above average and several sites were more than 3 °C above average, with the mean daily minimum of 21.3 °C observed at Pearce RAAF being 3.8 °C above the long term average.

Very warm overnight conditions were experienced across Perth during the second half of the month, with nearly all sites observing minimum temperatures of over 20 °C from the 14th through to the end of the month. Perth Metro observed 15 consecutive nights with a minimum temperature of 20 °C or more during February (14th to 25th), which is the longest hot spell of this kind at the Perth Metro site breaking the previous record of 13 nights observed in 1985 (17 February to 1 March) and in 1990 (23 February to 7 March). Forecast minima suggest this run could extend well into the first week of March.

Perth Metro's mean daily minimum temperature in February was 21.0 °C, which is 4th warmest on record for February since a mean minimum of 22.7 °C was recorded in 1985. The average for February is 18.1 °C. Daily minima ranged from a mild 15.8 °C on the 2nd to a hot 25.3 °C on the 28th.

Wind and sunshine

A strong pressure gradient over the south of WA caused fresh to strong and gusty easterly winds on 5 and 6 February 2011, with winds easing during the afternoon of the 7th. Sustained winds of 35 to 45 km/h, with gusts of 75 to 85 km/h at times, were observed in the Perth hills and foothills. The strong winds caused very high to severe fire dangers and significant bushfires at Redhill and Roleystone/Kelmscott destroyed or damaged over 100 homes. Bickley observed the highest wind gust of February 2011 during this event with 87 km/h on the 5th.

Easterly winds were stronger than normal across the Perth Metro area during February 2011, with a significant reduction in the strength and occurrence of the sea breeze at coastal locations.

Perth recorded an average daily sunshine of 11.3 hours in February, which was the sunniest February since 11.5 hours per day was recorded in 2002, and above the average of 10.9 hours per day.

Other Phenomena

The average dew-point temperature, a measure of the moisture content of the air (the temperature to which air - at constant atmospheric pressure - must be cooled in order for dew to occur) at Perth Metro during February 2011 was 14.8 °C, which is 1.5 °C above normal, and given the coincident hot air temperatures led to very uncomfortable conditions across Perth during the month.

Severe thunderstorms developed in the afternoon of 28 February in the north, east and south of Perth in a hot, moist and unstable atmosphere. The worst affected suburbs were Ellenbrook, Middle Swan, Midland, Mundaring and Kalamunda, with reports of damage, localised flooding and loss of power.

Further information

Media
(03) 9669 4057
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Extremes in February 2011
Hottest day 40.9 °C at Pearce RAAF on the 27th
Warmest days on average 35.9 °C at Gosnells City
Coolest days on average 30.1 °C at Rottnest Island
Coldest day 25.5 °C at Rottnest Island on the 1st
Coldest night 12.6 °C at Bickley on the 6th
Coolest nights on average 17.9 °C at Bickley
Warmest nights on average 21.7 °C at Rottnest Island
Warmest night 26.8 °C at Champion Lakes on the 28th
Wettest overall 1.2 mm at Pearce RAAF
1.2 mm at Serpentine
Wettest day 1.2 mm at Pearce RAAF on the 1st
Highest wind gust 87 km/h at Bickley on the 5th

Record lowest total February rainfall
Total rainfall
for February 2011 (mm)
Previous driest
for February
Years of
record
Average for
February
Garden Island HSF 0.0 0.2 in 2002 10 9.5



Record highest February mean daily maximum temperature
Mean daily maximum
temperature
for February 2011 (°C)
Previous warmest
for February
Years of
record
Average for
February
Jandakot Aero 34.9 34.4 in 1996 21 31.3
Gosnells City 35.9 35.8 in 1996 18 32.8
Swanbourne 34.0 32.5 in 1996 17 30.2

Highest February mean daily maximum temperature for at least 10 years
Mean daily maximum
temperature
for February 2011 (°C)
Most recent February
at least this warm
Years since
warmer
Average for
February
Bickley 32.7 33.8 in 1996 15 30.5
Pearce RAAF 35.6 36.9 in 1996 15 33.2
Perth Airport 34.9 35.7 in 1996 15 31.8
Perth Metro* 34.2 34.6 in 1996 15 31.3



Record highest February mean daily minimum temperature
Mean daily minimum
temperature
for February 2011 (°C)
Previous warmest
for February
Years of
record
Average for
February
Jandakot Aero 20.5 18.5 in 2008 21 16.8
Rottnest Island 21.7 21.6 in 1985 117 19.0
Bickley 17.9 17.5 in 1996 17 15.6
Swanbourne 21.0 19.9 in 1996 17 18.4

Highest February mean daily minimum temperature for at least 10 years
Mean daily minimum
temperature
for February 2011 (°C)
Most recent February
at least this warm
Years since
warmer
Average for
February
Perth Airport 20.8 21.4 in 1985 26 17.4
Medina Research Centre 20.6 20.7 in 1985 24 17.4



Summary statistics for February 2011
Maximum temperatures
for February
(°C)
Minimum temperatures
for February
(°C)
Rainfall
for February
(millimetres)
Mean for
February
2011
Diff
from
average
Highest for
February
2011
Mean for
February
2011
Diff
from
average
Lowest for
February
2011
Total for
February
2011
Average
for
February
Rank of
February
2011
Fraction of
February
average
Bickley 32.7 +2.2 37.9 27th 17.9 +2.3 12.6 6th 0.4 20.0 low 2%
Champion Lakes 34.1   39.2 28th 21.5   16.5 6th 0.2
Garden Island HSF 31.8   37.5 21st 21.5   16.6 6th 0 9.5 lowest 0%
Gosnells City 35.9 +3.1 40.6 28th     18.0 5th 0.2 15.5 low 1%
Jandakot Aero 34.9 +3.6 39.6 16th 20.5 +3.7 14.0 2nd 0 16.8 lowest 0%
Medina Research Centre 34.1 +2.8 40.0 16th 20.6 +3.2 15.2 2nd 0 20.3 lowest 0%
Pearce RAAF 35.6 +2.4 40.9 27th 21.2 +3.7 15.5 2nd 1.2 12.0 low 10%
Perth Airport 34.9 +3.1 40.1 28th 20.8 +3.4 16.2 6th 0.4 14.6 low 3%
Perth Metro* 34.2 +2.9 39.0 16th 21.0 +2.9 15.8 2nd 0.4 12.7 low 3%
Rottnest Island 30.1 +3.0 35.7 21st 21.7 +2.4 16.5 6th 0 7.3 lowest 0%
Swanbourne 34.0 +3.8 39.6 28th 21.0 +2.6 15.9 6th 0.4 6.3 low 6%

Daily maximum temperature
Central Coast (09)12345678910111213141516171819202122232425262728
Bickley29.633.436.033.727.027.429.430.733.332.129.728.830.932.136.436.431.531.734.127.434.133.632.432.937.237.437.937.1
Champion Lakes31.234.736.934.828.729.431.433.033.634.031.430.532.434.337.537.833.233.534.329.736.035.234.734.638.537.037.239.2
Garden Island HSF26.127.429.928.929.631.133.931.226.235.634.332.832.431.129.033.635.129.730.029.337.535.634.636.331.632.130.435.0
Gosnells City32.635.738.036.730.434.034.435.236.032.532.033.738.539.234.534.036.037.435.636.739.038.439.540.6
Jandakot Aero30.834.335.836.630.430.433.234.032.635.833.032.433.934.937.039.634.733.435.229.837.737.435.836.237.837.237.139.5
Medina Research Centre31.032.335.536.030.231.233.533.431.535.932.832.534.035.031.440.035.532.834.029.938.237.836.336.8
Pearce RAAF32.336.239.837.130.131.032.834.834.935.933.632.333.035.339.039.934.634.037.330.936.736.334.734.239.539.640.939.7
Perth Airport30.733.837.037.029.730.332.833.832.535.332.531.933.735.137.639.534.434.335.830.636.936.735.236.038.737.638.140.1
Perth Metro29.832.535.534.429.630.132.433.831.135.132.331.732.934.336.339.034.433.834.130.336.336.234.935.337.536.237.439.0
Rottnest Island25.526.127.526.628.229.230.630.127.128.231.730.830.129.728.730.031.430.528.328.535.733.631.333.733.232.231.333.7
Swanbourne29.131.730.632.131.231.734.334.128.636.534.033.334.035.135.338.436.232.532.030.137.937.536.336.736.132.134.939.6

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


Daily minimum temperature
Central Coast (09)12345678910111213141516171819202122232425262728
Bickley13.915.716.118.914.912.614.719.716.817.317.315.714.217.820.021.518.318.019.117.618.017.818.020.020.623.819.523.1
Champion Lakes17.619.619.922.418.916.518.622.320.920.820.719.618.321.523.325.621.922.121.621.222.421.821.924.024.424.123.226.8
Garden Island HSF16.820.320.222.418.616.619.122.420.521.120.520.018.621.822.924.721.922.222.221.022.922.222.523.324.724.022.925.1
Gosnells City19.220.422.918.021.120.819.518.521.722.822.222.122.021.021.022.124.225.225.024.023.7
Jandakot Aero16.614.019.722.318.016.018.519.918.820.720.519.318.121.422.323.121.520.420.021.022.121.120.523.524.321.322.525.5
Medina Research Centre16.015.219.422.519.216.018.521.619.920.920.719.818.221.822.425.321.521.021.221.022.421.420.623.824.1
Pearce RAAF18.515.520.122.818.416.019.622.920.620.420.619.518.721.323.824.621.821.319.721.222.921.221.725.325.620.423.526.4
Perth Airport17.917.219.822.818.316.218.420.919.820.720.619.217.821.323.124.921.720.918.621.122.020.319.923.824.521.323.326.6
Perth Metro17.915.819.722.918.416.018.321.620.120.920.519.317.921.122.324.621.821.421.521.021.921.221.423.824.522.923.125.3
Rottnest Island17.219.920.822.918.516.519.222.520.721.620.520.018.821.723.224.021.922.422.921.322.722.722.724.024.924.223.724.9
Swanbourne17.117.418.822.718.015.918.621.819.121.220.619.518.021.322.723.421.421.521.121.122.221.721.724.024.823.423.025.5

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


Daily rainfall
Central Coast (09)12345678910111213141516171819202122232425262728
Bickley 0.2 - - - - - - - - 0.2 - - - - - - - - - - - - - - - - -
Champion Lakes 0.2 - - - - - - - - - - - - - - - - - - - - - - - - - - -
Garden Island HSF - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Gosnells City 0.2 - - - - - - - - - - - - - - - - - - - - - - - - - - -
Jandakot Aero - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Jarrahdale - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Medina Research Centre - - - - - - - - - - - - - - - - - - - - - - - - -


Pearce RAAF 1.2 - - - - - - - - - - - - - - - - - - - - - - - -
- -
Perth Airport 0.4 - - - - - - - - - - - - - - - - - - - - - - - - - - -
Perth Metro 0.4 - - - - - - - - - - - - - - - - - - - - - - - - - - -
Rottnest Island - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Serpentine 0.2 - - - - - - - - - - - - - - - - - - - - - - - - - - 1.0
Swanbourne 0.4 - - - - - - - - - - - - - - - - - - - - - - - - - - -

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.


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 1 pm on Wednesday 2 March 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 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
(03) 9669 4057
Enquiries