Perth Monthly Climate Summary: August and Winter 2006
Perth's driest and equal warmest winter on record
Friday 1 September, 2006
August Rainfall - below average: The city received 124.8
mm of rainfall over 17 days in August compared with the average of 135
mm over 16 days. The wettest day in August 2006 was the 15th when 27.0
mm was recorded. Last August Perth registered 124.6 mm on 12 days.
Winter Rainfall - record low: The city received a record low winter rainfall
of 230.4 mm over 35 days in 2006, compared with the average of 485 mm
over 50 days. The previous driest winter was 260.0 mm on 40 days in 1940.
Last winter, Perth recorded 438.4 mm over 45 days. Rainfall totals for
individual months this winter were: June 24.6 mm (average 179 mm), July
81.0 mm (average 171 mm) and August 124.8 mm (average 135 mm). The wettest
day in winter was 15 August when 27.0 mm of rain fell.
|
Perth's top 10 driest winter's
|
|||
|
Season
|
Rainfall (mm)
|
Rain Days
|
Ranking
|
|
2006
|
230.4
|
35
|
1
|
|
1940
|
260.0
|
40
|
2
|
|
1881
|
303.2
|
39
|
3
|
|
1971
|
306.7
|
47
|
4
|
|
1877
|
307.6
|
48
|
5
|
|
1979
|
314.0
|
45
|
6
|
|
1914
|
316.7
|
43
|
7
|
|
1977
|
333.2
|
46
|
8
|
|
1894
|
333.7
|
50
|
9
|
|
1976
|
341.8
|
40
|
10
|
August mean daily maximum temperature - well above average:
Perth's mean daily maximum temperature in August was 20.2°C making
it the second highest mean maximum temperature for August on record. The
warmest August was 20.3°C in 1902 with the average for August being
18.5°C. Daily maxima ranged from a cool 16.0°C on the 16th to
a warm 26.7°C on the 29th.
Winter mean daily maximum temperature: The mean daily maximum
temperature for Perth this winter of 19.7°C was the equal highest
mean daily maximum temperature on record, also recorded in 1976 and 1983.
The average for winter is 18.6°C. Last winter the mean daily maximum
temperature was 18.3°C. Daily values ranged from a cold 14.6 degrees
on 21 July to a warm 26.7°C on the 29 August.
August mean daily minimum temperature - above average: Perth's
mean daily minimum temperature in August was 9.7°C, compared with
the average of 8.1°C. Daily minima ranged from a cold 3.1°C on
the 17th to a warm 17.0°C on the 7th, the highest daily minimum temperature
on record for August for Perth. The previous record minimum was 16.6°C
on 13 August 1976.
Winter mean daily minimum temperature: The mean daily minimum
temperature for Perth this winter of 7.4°C was below the average of
8.3°C. This was the second lowest winter mean daily minimum temperature
recorded at the official Perth metropolitan observation site at Mt Lawley.
Last winter the mean daily minimum temperature was 7.9°C. Daily minima
ranged from a cold −0.7°C on 17 June, the lowest temperature ever
recorded at the Mt Lawley site, to a warm 17.0°C on 7 August.
Mean daily sunshine hours: Perth's mean daily sunshine hours this winter was 7.1, which was above the long term average of 6.3 hours and the second sunniest winter on record.
| August monthly mean temperature and sunshine | |||||||
|---|---|---|---|---|---|---|---|
| Element |
2006 |
Long- term Average |
Highest |
Year |
Lowest |
Year | Records Commence |
| Maximum Temperature (°C) |
20.1
|
18.5
|
20.3
|
1902
|
16.3
|
1932
|
1897
|
| Minimum Temperature (°C) |
9.7
|
8.1
|
11.5
|
1977/1983
|
6.9
|
1956/2001
|
1897
|
| Sunshine # (hours per day) |
6.9
|
7.1
|
8.4
|
1902
|
4.2
|
1945
|
1898
|
| August rainfall and rain days | |||||||
| Element | 2006 | Long-term Average | Highest | Year | Lowest | Year | Records Commence |
|
Rainfall (mm)
|
124.8
|
135
|
318.3
|
1945
|
11.8
|
1902
|
1876
|
|
Rain days
|
17
|
16
|
29
|
1955
|
4
|
1902/1978
|
1876
|
# This is a preliminary figure based on the available data at the time of issue of this summary. Please check updated mean sunshine hours from Daily Weather Observations for Perth in early September.
| August daily extremes | |||||
|---|---|---|---|---|---|
| Element | 2006 | Date | Extreme | Date |
Records Commence |
|
Highest daily maximum (°C)
|
26.7
|
29/08/2006
|
27.8
|
21/08/1940
|
1897
|
|
Lowest daily maximum (°C)
|
16.0
|
16/08/2006
|
9.9
|
05/08/1951
|
1897
|
|
Highest daily minimum (°C)
|
17.0
|
07/08/2006
|
16.6
|
13/08/1976
|
1897
|
|
Lowest daily minimum (°C)
|
3.1
|
17/08/2006
|
1.3
|
21/08/2000
|
1897
|
|
Wettest 24 hours to 9am (mm)
|
27.0
|
15/08/2006
|
73.9
|
14/08/1945
|
1876
|
| Winter mean temperature and sunshine | |||||||
|---|---|---|---|---|---|---|---|
| Element |
Winter 2006 |
Long- term Average |
Highest |
Year |
Lowest |
Year | Records Commence |
| Maximum Temperature (°C) |
19.7
|
18.6
|
19.7
|
1976/1983
|
16.5
|
1916/1956
|
1897
|
| Minimum Temperature (°C) |
7.4
|
8.3
|
11.0
|
1964/1983
|
6.6
|
2001
|
1897
|
| Sunshine (hours per day) |
7.1
|
6.3
|
7.2
|
2001
|
4.1
|
1926
|
1898
|
| Winter rainfall and rain days | |||||||
| Element | Winter 2006 | Long-term Average | Highest | Year | Lowest | Year | Records Commence |
|
Rainfall (mm)
|
230.4
|
485
|
957.1
|
1945
|
260.0
|
1940
|
1876
|
|
Rain days
|
35
|
50
|
68
|
1926
|
35
|
1902
|
1876
|
| Winter daily extremes | |||||
|---|---|---|---|---|---|
| Element | Winter 2006 |
Date | Extreme | Date |
Records Commence |
|
Highest daily maximum (°C)
|
26.7
|
29/08/2006
|
28.1
|
05/06/1975
|
1897
|
|
Lowest daily maximum (°C)
|
14.6
|
21/07/2006
|
8.8
|
26/06/1956
|
1897
|
|
Highest daily minimum (°C)
|
17.0
|
07/08/2006
|
18.7
|
12/06/1988
|
1897
|
|
Lowest daily minimum (°C)
|
−0.7
|
17/06/2006
|
0.0
|
*Twice
|
1897
|
|
Wettest 24 hours to 9am (mm)
|
27.0
|
15/08/2006
|
99.1
|
10/06/1920
|
1876
|
* Denotes the lowest all-time minimum temperature on record on the following dates: 15 July 1997 and 27 July 1998
|
Recent winters in Perth
|
|||||
|
Season
|
Mean Maximum(°C)
|
Mean Minimum(°C)
|
Total Rainfall (mm)
|
Rain Days
|
Mean Sunshine (hours per day)
|
|
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
|
50
|
6.1
|
|
2004
|
18.4
|
8.4
|
411.4
|
52
|
6.3
|
|
2005
|
18.3
|
7.9
|
438.4
|
45
|
6.2
|
|
2006
|
19.7
|
7.4
|
230.4
|
35
|
7.1
|
Climate of Perth in September
September is the first month of spring and in Perth a warm drying trend is often experienced. Monthly rainfall and the number of wet days generally decreases, whilst maximum and minimum temperatures and the number of sunshine hours increases.
| September monthly mean temperatures and sunshine | ||||||
|---|---|---|---|---|---|---|
| Element | Average | Highest | Year | Lowest | Year |
Records |
| Maximum temperature (°C) |
20.0
|
22.6
|
1987
|
16.8
|
1915
|
1897
|
| Minimum temperature (°C) |
9.4
|
12.4
|
1988
|
8.0
|
2004
|
1897
|
|
Sunshine |
7.7
|
8.8
|
Many
|
4.9
|
1907
|
1898
|
| September rainfall and rain days | ||||||
|
Element
|
Average
|
Highest
|
Year
|
Lowest
|
Year
|
Records Commence
|
| Rainfall (mm) |
81
|
199.1
|
1923
|
8.7
|
1916
|
1876
|
| Rain days |
15
|
26
|
1915
|
4
|
1877
|
1876
|
|
September daily extremes
|
|||||
|---|---|---|---|---|---|
|
Element
|
Highest
|
Date
|
Lowest
|
Date
|
Records Commence
|
|
Maximum temperature (°C)
|
32.7
|
30/09/1918
|
11.4
|
17/09/1917
|
1897
|
|
Minimum temperature (°C)
|
19.5
|
08/09/1916
|
1.5
|
* Twice
|
1897
|
|
Rainfall 24 hours to 9am (mm)
|
51.8
|
14/09/1984
|
n/a
|
n/a
|
1876
|
* Denotes the lowest minimum temperature for September on record on the following dates: 1 and 10 September 2005.
Warm days in September: On average, Perth can expect two days when the maximum temperature is 25°C or higher. The record is 10 days in Perth's warmest September on record, 1987, when the mean maximum temperature was 22.6°C.
Cold days in September: On average, Perth can expect approximately one day every five years when the maximum temperature is 15°C or lower. The record is four days in 1903 whilst there were no such days in 2005.
Cold nights in September: On average, Perth can expect three nights each September when the minimum is 5°C or lower. The record is seven nights in 2004 and there were three such nights in 2005.
Earliest 32-degree day of the season (hot day): The earliest 32-degree maximum temperature of the season was on 18 September 1988, when 32.3°C was recorded, the second highest maximum temperature for September on record.
|
September top 10 hottest days
|
September top 10 coldest days
|
||||
|---|---|---|---|---|---|
|
Position
|
Date
|
Max temp
(°C) |
Position
|
Date
|
Max temp
(°C) |
|
1
|
30 September 1918
|
32.7
|
1
|
17 September 1917
|
11.4
|
|
2
|
18 September 1988
|
32.3
|
2
|
04 September 1931
|
11.6
|
|
3
|
22 September 1961
|
32.2
|
3
|
01 September 1931
|
12.1
|
|
4
|
26 September 1961
|
31.3
|
4
|
16 September 1937
|
12.5
|
|
5
|
14 September 1987
|
30.9
|
5
|
14 September 1947
|
12.7
|
|
6
|
28 September 1990
|
30.7
|
6
|
17 September 1915
|
12.9
|
|
6
|
20 September 1994
|
30.7
|
6
|
19 September 1923
|
12.9
|
|
8
|
12 September 1939
|
30.6
|
6
|
12 September 1950
|
12.9
|
| 8 |
21 September 1954
|
30.6
|
9 |
20 September 1904
|
13.0
|
|
8
|
27 September 1954
|
30.6
|
10
|
12 September 1916
|
13.1
|
|
-
|
-
|
-
|
10
|
10 September 1925
|
13.1
|
|
September top 10 warmest nights
|
September top 10 coldest nights
|
||||
|---|---|---|---|---|---|
|
Position
|
Date
|
Min temp
(°C) |
Position
|
Date
|
Min temp
(°C) |
|
1
|
08 September 1916
|
19.5
|
1
|
01 September 2005
|
1.5
|
|
2
|
30 September 1918
|
18.9
|
1
|
10 September 2005
|
1.5
|
|
3
|
02 September 1959
|
18.3
|
3
|
11 September 2004
|
1.7
|
|
4
|
27 September 1936
|
17.8
|
4
|
23 September 1998
|
1.8
|
|
5
|
20 September 1930
|
17.7
|
5
|
16 September 2002
|
2.0
|
|
6
|
29 September 1900
|
17.6
|
6
|
03 September 1994
|
2.3
|
|
7
|
20 September 1985
|
17.5
|
7
|
06 September 1956
|
2.6
|
|
7
|
28 September 1985
|
17.5
|
8
|
04 September 1998
|
2.8
|
| 9 |
30 September 1898
|
17.4
|
9 |
08 September 1952
|
3.1
|
|
10
|
28 September 1930
|
17.2
|
9
|
05 September 1999
|
3.1
|
| 10 |
26 September 1936
|
17.2
|
- |
-
|
-
|
|
10
|
28 September 1998
|
17.2
|
-
|
-
|
-
|
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) and Glenn Cook Western Australia Climate Services Centre
on, tel: (08) 9263 2222, office hours.