Tuesday, 3 March 2009 - Seasonal Climate Summary for Perth - Product Code: IDCKGC21L0

A very warm summer in Perth

Mean daily maximum temperature - very much above average: The mean daily maximum temperature this summer was 30.7°C, which is the equal 10th warmest summer on record for Perth. The average is 30.1°C.  Last summer the mean daily maximum temperature was 31.0°C, Perth's equal fourth warmest summer on record. Daily values this summer ranged from a mid 21.9°C on 10 December 2008 to a very hot 41.8°C on 16 January 2009.

Perth's top 10 mean maximum temperatures
for summer
Year/s
Mean Maximum Temperatures (°C)
Departure from normal
Ranking
1977/78
32.0
+1.9
1
1931/32
31.4
+1.3
2
1961/62
31.3
+1.2
3
1960/61
31.0
+0.9
4
2007/08
31.0
+0.9
4
1994/95
30.9
+0.8
5
1995/96
30.9
+0.8
5
1999/00
30.9
+0.8
5
1997/98
30.8
+0.7
9
1975/76
30.7
+0.6
10
1979/80
30.7
+0.6
10
2008/09
30.7
+0.6
10

Mean daily minimum temperature - near average: The mean daily minimum temperature for Perth this summer was 17.4°C, compared to the average of 17.3°C. Daily minima ranged from a cool 10.0°C on 26 February 2009 to a warm 23.7°C on 11 February 2009. Last summer the mean daily minimum temperature was 17.8°C.

Rainfall - near average: This summer the rainfall in Perth was near average. From December to February, Perth received 20.0 mm over 11 days compared with the average of 36 mm on about 9 days. It was Perth's driest summer since 2004/2005, then 5.6 mm on 6 days. Last summer, Perth recorded 65.6 mm over 9 days. Rainfall totals for individual months this summer were: December 11.6 mm (average 13 mm), January 0.2 mm (average 10 mm) and February 8.2 mm (average 13 mm). The wettest day was on 26 February 2009 when 7.6 mm of rain was recorded.

Summer mean temperature and sunshine
Element

Summer 2008/09

Long- term Average

Highest

Year

Lowest

Year Records Commence
Maximum
Temperature (°C)
30.7
30.1
32.0
1977/78
26.5
1901/02
1897
Minimum Temperature (°C)
17.4
17.3
20.3
1977/78
15.4
1901/02
1897
Sunshine
(hours per day)
11.3
11.4
12.1
1997/98
8.7
1922/23
1898
Summer rainfall and rain days
Element Summer 2008/09 Long-term Average Highest Year Lowest Year Records Commence
Rainfall (mm)
20.0
36
180.4
1954/55
0.8
1974/75
1876
Rain days
11
8.6
20
1913/14
2
3 years
1876

Summer daily extremes
Element Summer 2008/09 Date Extreme Date

Records Commence

Highest daily maximum (°C)
41.8
16/01/2009
46.2
23/02/1991
1897
Lowest daily maximum (°C)
21.9
10/12/2008
14.9
17/12/1952
1897
Highest daily minimum (°C)
23.7
11/02/2009
29.3
* 3 years
1897
Lowest daily minimum (°C)
10.0
26/02/2009
7.9
07/12/2007
1897
Wettest 24 hours to 9am (mm)
7.6
26/02/2009
120.6
09/02/1992
1876

* Denotes highest February minimum temperature on record has occurred on the following dates: 6 February 1898, 8 February 1933 and 3 February 1962.

Past summers in Perth 1994/95−2008/09
Season
Mean Maximum(°C)
Mean Minimum(°C)
Total Rainfall (mm)
Rain Days
Mean Sunshine (hour)
1994/95
30.9
18.1
12.0
3
11.7
1995/96
30.9
17.4
6.2
5
11.6
1996/97
30.2
17.7
24.8
11
11.5
1997/98
30.8
17.3
1.8
2
12.1
1998/99
30.4
17.8
60.8
9
11.6
1999/00
30.9
18.3
146.2
13
11.1
2000/01
29.9
17.3
9.8
8
11.3
2001/02
29.3
16.3
31.4
10
11.4
2002/03
30.6
17.5
16.2
12
11.4
2003/04
30.4
17.5
7.6
6
11.6
2004/05
30.0
16.7
5.6
6
11.5
2005/06
28.0
16.2
54.0
14
10.6
2006/07
29.9
16.9
27.8
11
11.0
2007/08
31.0
17.8
65.6
9
10.8
2008/09
30.7
17.4
20.0
11
11.3

Note: 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 Perth (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 Perth (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.

Further information:
John Relf (JR), or Glenn Cook tel: (08) 9263 2222 on weekdays.