Wednesday ,1 September 2004
MONTHLY CLIMATE SUMMARY - WESTERN AUSTRALIAN REGIONAL
OFFICE
Below average winter rainfall in Perth
Rainfall: Winter rainfall this year was below average.
From June to August, Perth received 411.4 millimetres over 52 days compared
with the average of 486 mm over 50 days. This winter was the driest since
the 384.8 mm in 2002. Last winter, 464.4 mm over 51 days was recorded.
Historically, winter rainfall has ranged from a low of 260.0 mm in 1940
to 957.1 mm in 1945. The wettest day this winter was 12 August when 26.4
mm was recorded. The rainfall for individual winter months was: June 123.2
mm (average 179 mm), July 112.6 mm (average 172 mm) and August 175.6 mm
(average 135 mm).
Mean daily maximum temperature: Perth's mean maximum
temperature this winter of 18.4 degrees Celsius was close to the long-term
average of 18.7 degrees. Last winter, the mean maximum temperature was
18.3 degrees. Daily maxima this winter ranged from a cold 13.3 degrees
on 28 August to a warm 24.6 degrees on 16 June.
Mean daily minimum temperature: Perth's mean minimum temperature
this winter was 8.4 degrees which matches the average of 8.4 degrees.
Last winter, the mean minimum temperature was 7.8 degrees. Daily minima
ranged from a cold 0.4 degrees on 26 July to a mild 15.3 degrees on 16
June. Perth recorded 20 cold nights this winter when the temperature was
5 degrees or less, which matches the long-term average of 20 nights.
Mean daily sunshine hours: Perth's mean daily sunshine hours this
winter was 6.3 hours, which matches the average of 6.3 hours. Last winter,
the figure was 6.1 hours.
| Winter mean temperature and sunshine |
| Element |
Winter 2004
|
Long-term Average† |
Highest
|
Year |
Lowest
|
Year |
Records Commence |
Maximum
Temperature (°C) |
18.4
|
18.7
|
19.7
|
1976,83
|
16.5
|
1916,56
|
1897
|
Minimum
Temperature (°C) |
8.4
|
8.4
|
11.0
|
1964,83
|
6.6
|
2001
|
1897
|
Sunshine
(hours/day)
|
6.3
|
6.3
|
7.2
|
2001
|
4.1
|
1926
|
1898
|
| Winter rainfall and rain days |
| Element |
Winter 2004 |
Long-term Average† |
Highest |
Year |
Lowest |
Year |
Records Commence |
|
Rainfall (mm)
|
411.4
|
486
|
957.1
|
1945
|
260.0
|
1940
|
1876
|
|
Rain days
|
52
|
50
|
68
|
1915,26
|
35
|
1902
|
1876
|
| Winter daily extremes |
| Element |
Winter 2004 |
Date |
Extreme |
Date |
Records Commence
|
|
Highest daily maximum (°C)
|
24.6
|
16/06/2004
|
28.1
|
05/06/1975
|
1897
|
|
Lowest daily maximum (°C)
|
13.3
|
28/08/2004
|
8.8
|
26/06/1956
|
1897
|
|
Highest daily minimum (°C)
|
15.3
|
16/06/2004
|
18.7
|
12/06/1988
|
1897
|
|
Lowest daily minimum (°C)
|
0.4
|
26/07/2004
|
0.0
|
* Twice
|
1897
|
|
Wettest 24 hours to 9am (mm)
|
26.4
|
12/08/2004
|
99.1
|
10/06/1920
|
1876
|
*Denotes the lowest minimum temperature for July on record on the
following dates: 15 July 1997 and 27 July 1998.
|
Past winters in Perth 1994-2004
|
|
Season
|
Mean Maximum°C
|
Mean Minimum°C
|
Total Rainfall (mm)
|
Rain Days
|
Mean Sunshine
|
| 1994 |
18.9
|
8.7
|
535.0
|
51
|
6.3
|
| 1995 |
18.3
|
8.6
|
512.4
|
52
|
6.1
|
| 1996 |
18.6
|
9.7
|
555.8
|
63
|
5.6
|
| 1997 |
18.8
|
7.6
|
361.6
|
41
|
6.9
|
| 1998 |
18.2
|
8.5
|
414.8
|
57
|
5.7
|
| 1999 |
19.2
|
8.6
|
401.6
|
48
|
6.7
|
| 2000 |
18.5
|
9.0
|
497.2
|
58
|
6.0
|
| 2001 |
19.1
|
6.6
|
382.2
|
42
|
7.2
|
| 2002 |
18.8
|
8.7
|
384.8
|
51
|
6.3
|
| 2003 |
18.3
|
7.8
|
464.4
|
51
|
6.1
|
| 2004 |
18.4
|
8.4
|
411.4
|
52
|
6.3
|
†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
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.
Further information:
John Relf (JR), Yanhui Blockley or John Cramb tel: (08) 9263 2222 or,
after hours, the senior forecaster.
© 2004 Bureau of Meteorology Perth Western Australia
|
