Thursday 1 June, 2006

MONTHLY CLIMATE SUMMARY - WESTERN AUSTRALIA REGIONAL OFFICE

Driest May for six years in Perth

Rainfall well below average: The city received 31.0 mm of rainfall over 9 days in May compared with the average of 120 mm over 12 days. This was Perth's driest May since the 26.4 mm in 2000. Historically, May rainfall has ranged from 14.1 mm in 1964 to 308.1 mm in 1879. Last May Perth registered 191.2 mm on 16 days. Total rainfall for January to May this year was 110.0 mm, making it the driest start to the year since the 90.0 mm in 1996.The average is 205 mm. Perth's driest January to May period was 64.3 mm in 1972. The wettest day in May 2006 was the 15th when 12.4 mm was recorded.

Mean daily maximum temperature near average: Perth's mean daily maximum temperature in May was 22.4 degrees Celsius, compared with the average of 22.3 degrees. Daily maxima ranged from a cool 16.6 degrees on the 29th to a warm 29.5 degrees on the 12th.

Mean daily minimum temperature well below average: Perth's mean daily minimum temperature in May was 8.9 degrees Celsius, compared with the average of 11.0 degrees. This was the lowest mean daily minimum temperature for May since the 8.8 degrees in 2000. Minima ranged from a cold 2.9 degrees on the 25th to a mild 15.5 degrees on the 15th.

Climate of Perth in June

June is Perth's wettest month of the year, on average. Cool and cloudy days are common. Some are cold, windy and showery, while others are sunny with light winds.

*Denotes the lowest minimum temperature for June on record on the following dates: 19 June 2003 and 2 June 2004.

Warm days in June: On average, Perth can expect eleven days when the maximum temperature is 20 degrees or more. The greatest number of such days in June was 21 days in 1983. Last June, Perth recorded eleven such days.

Cold days in June: On average, Perth can expect one day when the maximum temperature is 15 degrees or less. The greatest number of such days in June was 10 in 1931 and 1955. Last June, Perth recorded three such days.

Cold nights in June: Perth has a mean of six cold nights when the minimum temperature is 5 degrees or lower. The greatest number of such nights was in 2001 with twelve. Last June, Perth recorded six such nights.

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:
Yanhui Blockley, John Cramb or Michelle Dal Pozzo, Climate Section, tel: (08) 9263 2222,office hours.