Warm August nights and days in the ACT

The ACT was warmer than normal in August this year and also had above-average rainfall, wind and sunshine.

Temperature: The average daily maximum temperature of 14.7 degrees Celsius in the ACT in August was well above the long-term average of 12.9 degrees. The mean daily minimum of 1.9 degrees was also well above the long-term average of 0.9. There were 16 frosts in August, two fewer than normal due to the higher daily minimum temperatures. The August mean daily temperature of 8.3 degrees was well above the long-term average of 6.9 and was the highest since 1998 when the mean daily temperature was 8.8 degrees.

Rainfall: A total of 67.8 millimetres of rain fell at Canberra airport over seven days in August, well above the average of 47.3 mm over 11 days. The rainfall in the 48-hour period ending 9am, 31 August, was the best general rain in the region since early December last year. It was the heaviest rainfall this year. Rainfall was generally above average across the ACT, with higher falls in the west and north of the territory. The highest reading was 115.0 mm at Corin Dam. The lowest was 48.6 mm at Wanniassa. While no thunderstorms were recorded at the airport (average one), some thunderstorm activity was reported in western and northern parts of the ACT on the night of 30 August. There was one report of hail (average zero), no reports of snow (average one) and only two days of fog (average four) in August.

Wind: The mean daily wind run in August was 241 kilometres a day, well above the long-term average of 207 km/day. There were five days of strong winds (average three) and one day of gale-force winds (average zero) on 13 August. The strongest wind gust at Canberra airport was 83 km/h on 13 August.

Other: Sunshine averaged 7.4 hours/day in August, much more than the long-term mean of 6.8 hr/day. Total evaporation for the month was 94.4 mm, considerably more than the long-term average of 79.2 mm. The mean daily pressure was 1015.5 hectopascals, much less than the long-term average of 1018.9 hPa.

Summary for Canberra airport, August 2004

Mean maximum temperature: 14.7°C (av 12.9°C)
Highest maximum temperature: 21.8°C (26 August)
Lowest maximum temperature: 8.0°C (3 August)
Mean minimum temperature: 1.9°C (av 0.9°C)
Highest minimum temperature: 8.8°C (30 August)
Lowest minimum temperature: minus 3.9°C (20 August)
Mean daily temperature: 8.3°C (av 6.9°C)
Lowest grass temperature: minus 7.9°C (2 August)
Total monthly rainfall: 67.8 mm (av 47.3 mm)
Total monthly evaporation: 94.4 mm (av 79.2 mm)
Mean daily sunshine: 7.4 hr/day (av 6.8 hr/day)
Mean daily pressure: 1015.5 hPa (av 1018.9 hPa)
Mean daily wind run (at 2 metres): 241 km/day (av 207 km/day)

Ends

Further information:
Clem Davis, Canberra Meteorological Office, tel: (02) 6249 6269, e-mail: c.davis@bom.gov.au