Wednesday, 4 January 2006

MONTHLY CLIMATE SUMMARY - ACT

A very dry, warm and sunny December in the ACT

December 2005 in the territory was characterised by higher than average temperatures and very dry conditions.

Rainfall: Canberra airport recorded 19.8 millimetres of rain for two days of the month, well below the December average of 52.8mm for seven days. Severe thunderstorm activity on the second day of December accounted for 16.6mm of the total rainfall while also producing a gust of 100 kilometres per hour at the airport. The wind caused extensive damage in the Fyshwick area and unfortunately, one death by a falling tree in Curtin. The highest rainfall recorded for the month was 32.8mm at Corin Dam and the lowest rainfall recorded was 16.4mm at Bruce.

There were three thunderstorms recorded at the airport, one less than average for December. Not all the storms carried rain and no hail was reported.

Temperature: The mean daily maximum temperature of 28.8 degrees Celsius exceeded the long-term average of 26.1°C and is the highest average since 1997 (29.6°C). The mean daily minimum temperature of 12°C was nearly one degree above the average. Ten days of 30°C or higher were recorded during the month, which is seven days more than the average for December. Four of these days were 35°C or higher, compared to the average of one. Overall the mean daily temperature, as an average of the daily maximum and minimum temperatures, was 20.5°C, well above the long-term figure of 18.7°C.

Other: The mean daily sunshine of 11.4 hours per day set a new record for the month, exceeding the average of 9.4 hours/day. The previous record of 11.2 hours of sunshine in a day was set in 1979.

The wind run for two metres of 255 kilometres per day was 40 km/day above the long-term average. There were five days of strong winds, (which is three days more than average), including one day of gale-force winds, of which the average for December is zero.

The dry and windy conditions during the month contributed to the evaporation of 310.4 millimetres surpassing the average of 250.5 mm. The average daily pressure of 1008.7 hectopascals was well below the average of 1011.3 hPa. No frosts or fogs were observed.

Summary for Canberra airport, December 2005

Mean maximum temperature: 28.8°C (av 26.1 °C)
Highest maximum temperature: 38.7 °C (on 31 December)
Lowest maximum temperature: 17.1 °C (on 3 December)
Mean minimum temperature: 12.0 °C (av 11.2°C)
Highest minimum temperature: 17.5 °C (on 24 December)
Lowest minimum temperature: 7.1 °C (on 20 December)
Lowest grass temperature: 3 °C (on 9 December)
Total rainfall: 19.8 mm (av 52.8 mm)
Total evaporation: 310.4 mm (av 250.5 mm)
Mean daily sunshine: 11.4 hours/day (av 9.4 h/day)
Mean daily pressure: 1008.7 hPa (av 1011.3 hPa)
Mean daily wind run (at 2 metres): 255 km/day (av 215 km/day)

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

Ends