Perth in spring 2010: Warmest spring on record

  • Very much below average rainfall.
  • Warmest spring in terms of mean maximum temperature.
  • Near average mean daily minimum temperature.

Rainfall

Rainfall totals for spring 2010 were generally in the 50-80 mm range, and 30% to 70% below the long-term average for spring. Following one of the driest winters on record, the Perth region again experienced a very dry season. Jandakot Aerodrome and Medina Research Centre both registered their lowest spring rainfall in 35 and 28 years of recording respectively.

Perth Metro recorded 75.8 mm during spring, which was Perth Metro's fourth driest spring on record, and driest spring since 1969; the driest spring being 34.5 mm in 1877. Rainfall totals for individual months this spring were: September 43.6 mm (average 80.9 mm), October 20.6 mm (average 52.4 mm) and November 11.6 mm (average 22.2 mm).

Perth Metro recorded 14 rain days this spring, which was the second lowest number of rain days for spring for Perth Metro, behind the 12 rain days in 1969. Last spring, Perth Metro recorded 125.2 mm on 37 rain days.

Maximum temperature

Mean maximum temperatures for spring 2010 in the Perth metropolitan area were generally in the 23 to 26 °C range, and 2 to 3 °C above average. It was the warmest spring on record for most sites in the Perth area, including Perth Metro and Rottnest Island, which both registered their warmest spring since comparable records commenced in 1897. The 19th November was the hottest day of the season for most of the metropolitan area, and on that day Medina Research Centre registered a daily maximum temperature of 41.4 °C, the highest temperature recorded in the Perth region in spring 2010, and the highest spring temperature in 26 years of record for Medina Research Centre.

Perth Metro's mean daily maximum temperature in spring 2010 was 25.3°C, which was Perth Metro's warmest spring since records commenced in 1897. Daily maxima ranged from a cool 16.5 °C on 12th September to a very hot 38.8 °C on 19th November. Perth Metro recorded 12 hot days (a hot day is a day when the daily maximum temperature is 32 °C or higher) this spring, which was the greatest number of hot days for Perth Metro for spring on record.

Minimum temperature

Averaged over the three months of spring 2010, minimum temperatures were near average in the Perth region, mostly in the 10 °C to 13 °C range and within 1 °C of normal.

Perth Metro's mean daily minimum temperature in spring 2010 was 11.5°C, which was close to the average of 11.6 °C. Daily minima ranged from a cold 2.4 °C on 13th September to a warm 23.0 °C on 19th November.

Wind & sunshine

Rottnest Island recorded the highest wind gust for spring with 87 km/h recorded during a cold front passage on 12th September.

Average sunshine recorded at Perth Airport for spring was 10.1 hours per day, which was the sunniest spring since records commenced in Perth in 1898. The previous spring record was 9.9 hours in 2007.

Further information

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Extremes in spring 2010
Hottest day 41.4 °C at Medina Research Centre on 19 Nov
Warmest days on average 26.2 °C at Gosnells City
Coolest days on average 22.4 °C at Rottnest Island
Coldest day 12.9 °C at Bickley on 8 Sep
Coldest night 0.5 °C at Jandakot Aero on 13 Sep
Coolest nights on average 9.8 °C at Jandakot Aero
Warmest nights on average 14.8 °C at Rottnest Island
Warmest night 24.9 °C at Pearce RAAF on 19 Nov
Wettest overall 93.8 mm at Mundaring
Wettest day 20.6 mm at Jarrahdale on 8 Sep
Highest wind gust 87 km/h at Rottnest Island on 12 Sep

Record lowest total spring rainfall
Total rainfall
for spring 2010 (mm)
Previous lowest
for spring
Years of
record
Average for
spring
Jandakot Aero 60.4 77.2 in 1994 35 162.9
Medina Research Centre 62.0 66.2 in 2000 28 149.8




Record highest spring temperature
Highest temperature
in spring 2010 (°C)
Previous highest
for spring
Years of
record
Average for
spring
Medina Research Centre 41.4 on 19 Nov 40.6 on 11 Nov 2003 26 22.8



Record highest spring mean daily maximum temperature
Mean daily maximum
temperature
for spring 2010 (°C)
Previous highest
for spring
Years of
record
Average for
spring
Perth Metro 25.3 24.0 in 2006 113 23.0
Rottnest Island 22.3 21.5 in 2006 113 20.5
Perth Airport 25.8 24.7 in 1969 66 22.8
Medina Research Centre 25.4 23.9 in 2006 23 22.8
Jandakot Aero 25.5 23.8 in 2006 20 22.7
Swanbourne 24.7 23.2 in 2006 17 22.1
Bickley 23.1 22.1 in 1994 16 21.0
Gosnells City 26.2 25.1 in 1994 15 23.9




Summary statistics for spring 2010
Maximum temperatures
for spring
(°C)
Minimum temperatures
for spring
(°C)
Rainfall
for spring
(millimetres)
Mean for
spring
2010
Diff
from
average
Highest for
spring
2010
Mean for
spring
2010
Diff
from
average
Lowest for
spring
2010
Total for
spring
2010
Average
for
spring
Rank of
spring
2010
Fraction of
spring
average
Bickley 23.1 +2.1 36.7 19 Nov 10.3 +0.6 3.0 13 Sep 76.4 227.4 v low 34%
Champion Lakes 24.8   38.0 19 Nov 12.6   4.8 13 Sep 54.2
Garden Island HSF 23.0   37.0 19 Nov 13.4   7.0 18 Oct 54.4
Gosnells City 26.2 +2.3 40.5 19 Nov     4.2 10 Sep 47.4 154.8 v low 31%
Jandakot Aero 25.5 +2.8 39.9 19 Nov 9.8 -0.2 0.5 13 Sep 60.4 162.9 lowest 37%
Medina Research Centre 25.4 +2.6 41.4 19 Nov 11.0 +0.2 2.2 3 Sep 62.0 149.8 lowest 41%
Pearce RAAF 25.9 +2.5 39.1 19 Nov 10.4 0.0 2.5 11 Sep 54.6 128.3 v low 43%
Perth Airport 25.8 +3.0 40.5 19 Nov 10.7 +0.1 2.7 13 Sep 60.6 141.6 v low 43%
Perth Metro 25.3 +2.3 38.8 19 Nov 11.4 -0.2 2.4 13 Sep 75.8 155.5 v low 49%
Rottnest Island 22.4 +1.9 35.3 19 Nov 14.8 +0.7 8.6 13 Sep 59.2 101.3 low 58%
Swanbourne 24.7 +2.6 39.5 19 Nov 12.6 +0.1 4.9 13 Sep 78.8 147.4 v low 53%

Notes

A Seasonal 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 2 pm on Wednesday 1 December 2010. 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 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