Record heat and near record dry in the ACT in April

Canberra this year recorded its highest April mean maximum temperature on record in a month when rainfall was the fourth lowest (for April) on record. On a national scale, it was the warmest April on record. All states except Tasmania recorded all-time highs for April mean maximum temperature.

Temperature: The ACT's mean daily April minimum of 7.9 degrees Celsius was well above the long-term mean of 6.6 degrees. The mean daily maximum of 24.5 degrees was also well above - 4.7 degrees above - the long-term mean of 19.8 degrees. It was the highest April mean daily maximum on record and beat the previous record of 22.6 degrees set in 1997. The overall mean April temperature was 16.2 degrees compared with the average of 13.2 degrees. It was the highest mean April temperature on record and beat the previous record of 15.3 degrees set in 1990 and 2002. Although four frosts were recorded for the month - which is average - the temperature at the screen (located 1.2 metres above the ground) only dropped below zero on one occasion. On 30 April the temperature fell to minus 1.2 degrees.

Rainfall: Only 6.8 millimetres of rain recorded over four days fell at Canberra airport in April. This was significantly below the average of 47.7 mm over seven days and the fourth lowest April total on record. The lowest April total is 0.8 mm in 1997. There were no thunderstorms recorded at the airport compared with the average of one day. Rainfall across the ACT was also very much below average. The highest recordings were 13.0 mm at Tidbinbilla and Corin Dam. The April wind run was 137 kilometres a day, less than the mean of 148 km/day. There were two days of strong winds compared with the average of one day. The strongest wind gust was 76 km/h on 3 April. Four fogs were recorded at the airport, which is average.

Other: The average daily sunshine in April was 8.6 hours a day, well above the long-term mean of 7.1 hr/day. Total evaporation was 130.8 mm, also well above the average of 107.8 mm. The average daily pressure was 1023.3 hectopascals, greater than the average of 1019.5 hPa.

Summary for Canberra airport, April 2005

Mean maximum temperature: 24.5°C (av 19.9°C)
Highest maximum temperature: 29.9°C (3 April)
Lowest maximum temperature: 18.6°C (15 April)
Mean minimum temperature: 7.9°C (av 6.6°C)
Highest minimum temperature: 15.9°C (11 April)
Lowest minimum temperature: minus 1.2°C (30 April)
Mean daily temperature: 16.2°C (av 13.2°C)
Lowest grass temperature: minus 5.8°C (30 April)
Total monthly rainfall: 6.8 mm (av 47.7 mm)
Total monthly evaporation: 130.8 mm (av 107.8 mm)
Mean daily sunshine: 8.6 hr/day (av 7.1 hr/day)
Mean daily pressure: 1023.3 hPa (av 1019.5 hPa)
Mean daily wind run (at 2 metres): 137km/day(av 148.0 km/day)

Further information:
Ken Batt, Canberra Meteorological Office, tel: (02) 6249 6269, e-mail: K.Batt@bom.gov.au

Ends