Driest summer in Perth since 1997/98

Rainfall well below average: This summer Perth received 5.6 millimetres of rainfall on 6 days compared with the average of 36 mm on 8 days. It was the driest summer since the 1.8 mm in 1997/98 and the ninth driest summer on record. Last summer, Perth recorded 7.6 mm on 6 days. Rainfall totals for individual summer months were: December 2.6 mm (average 13 mm), January Nil (average 10 mm) and February 3.0 mm (average 13 mm). The wettest day was 27 February when 1.6 mm of rain fell.

Mean daily maximum temperatures near average: The mean daily maximum temperature this summer was 30.0 degrees Celsius, which is close to the average of 30.3 degrees. Last summer the mean daily maximum temperature was 30.2 degrees. Daily values ranged from a mild 21.6 degrees on 5 December to a very hot 42.0 degrees on 15 February.

Mean daily minimum temperatures near average: The mean daily minimum temperature this summer was 16.7 degrees, which is close to the average of 17.4 degrees. Last summer the mean minimum temperature was 17.5 degrees. Daily minima ranged from a cool 10.2 degrees on 1 and 4 December to a warm 22.7 degrees on 26 December.

Mean daily sunshine hours near average: Perth's mean daily sunshine hours this summer was 11.6 hours, which was close to the average of 11.5 hours.

Summer mean temperature and sunshine
Element	2004/05	Long term Average	Highest	Year	Lowest	Year	Records Commence
Maximum Temperature (°C)	30.0	30.3	32.0	1977/78	26.4	1901/02	1897
Minimum Temperature (°C)	16.7	17.4	20.3	1977/78	15.4	1901/02	1897
Sunshine (hours per day)	11.6	11.5	12.2	1997/98	8.7	1922/23	1898
Summer rainfall and rain days
Element	2004/05	Long term Average	Highest	Year	Lowest	Year	Records Commence
Rainfall (mm)	5.6	36	180.4	1954/55	0.8	1974/75	1876
Rain days	6	8	20	1913/14	2	3 years	1876

 

Summer daily extremes
Element	2004/05	Date	Extreme	Date	Records Commence
Highest daily maximum (°C)	42.0	15/02/2005	46.2	23/02/1991	1897
Lowest daily maximum (°C)	21.6	05/12/2004	14.9	17/12/1952	1897
Highest daily minimum (°C)	22.7	26/12/2004	29.3	3 years	1897
Lowest daily minimum (°C)	10.2	01 & 04/12/2004	8.4	02/12/2002	1897
Wettest 24 hours to 9am (mm)	1.6	27/02/2005	120.6	09/02/1992	1876

Past summers in Perth 1994-2005
Season	Mean Maximum(°C)	Mean Minimum(°C)	Total Rainfall (mm)	Rain Days	Mean Sunshine (hour)
1994/95	30.8	18.1	12.0	3	11.7
1995/96	30.8	17.4	6.2	5	11.6
1996/97	30.2	17.6	24.8	11	11.5
1997/98	30.7	17.3	1.8	2	12.2
1998/99	30.4	17.8	60.8	9	11.6
1999/00	30.9	18.2	146.2	13	11.0
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	30.2	17.5	7.6	6	11.6
2004/05	30.0	16.7	5.6	6	11.6

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), or John Cramb tel: (08) 9263 2222.