Monday, 2 March 2009 - Seasonal Climate Summary for Canberra rainfall extremes - Product code IDCKGC25x0

Canberra has very warm summer with a dry end

Summary 

Canberra and the ACT had a very warm summer with slightly above average rainfall. However, summer ended on a very dry note with only 6 mm of rain in the last 5 weeks of the season.

Main points 

  • Generally close to average rainfall, but some suburbs well above average rainfall
  • Severe thunderstorms in some suburbs
  • Very warm days, well above average maximum temperatures
  • Mild nights with above average minimum temperatures
  • Sunny summer with well above average sunshine hours

An archive of previous seasonal summaries for Canberra rainfall extremes is also available, as are summaries for other states and many other climate summaries and diagnostics.

Rainfall

The total summer rainfall of 179.2 mm at Canberra Airport was slightly above the historical summer average1 of 167.3  mm. Most of the season's rainfall occurred during December with January and February generally dry months. There were 18 rain days during summer, below the historic average of 22 rain days. A significant proportion of summer's rainfall occurred on 13 December when an intense low pressure system passed over southern NSW. Most other falls were from thunderstorms, especially 27 December (when up to 56 mm fell in some Canberra suburbs) and 22 January (up to 38 mm in some suburbs).

The wettest location in the ACT during summer was the suburb of Curtin (Deakin West) with a total of 241.2 mm, well above the historic summer average of 186 mm. The driest location was at Kingston with a total of 139.2 mm.

Temperatures

Warm to very warm days prevailed in the ACT over summer, especially during late January and early February when there were heatwave conditions. The average1 maximum temperature for summer at Canberra Airport was 28.3°C, which is 1.2°C above the historical summer average of 27.1°C. This contrasts sharply with last summer when below average temperatures were recorded.

Canberra had 10 very hot days (over 35°C) during January and February compared to the historic average of only 4 days over 35°C. This has only been exceeded in the 69 year record by 12 days in 2004 and 1981, and 11 days in 1983 and 1968. The warm conditions were partly due to prevailing warm winds from the NW quadrant (67% of the time during the day), an abundance of sunny days and few significant cool changes.

Generally mild nights prevailed in Canberra during summer. The average minimum temperature at Canberra Airport was 13.4°C, which is above the historical summer average of 12.5°C. It marks the 9th consecutive summer with above average minimum temperatures at Canberra Airport. Nights were particularly warm during the heatwave of late January and early February. On 7 and 8 February there were 2 consecutive nights when the temperature remained above 20°C. This has only been exceeded by 4 consecutive nights above 20°C back in February 1973.

The highest temperature in the ACT during summer was 40.0°C at Canberra Airport on 7 and 8 February while the lowest temperature was 5.6°C at Canberra Airport on 2 December and −1.0°C at Mount Ginini AWS on 20 December. The hottest night was 21.1°C at Tuggeranong AWS on 6 February and at Canberra Airport on 8 February.

Wind

The prevailing winds at Canberra Airport during summer afternoons were between north and west (67% of time). The highest wind gust was 106 km/h at Canberra Airport during a severe thunderstorm on 20 January. This is the strongest wind gust recorded in January since 1980 and the strongest in any month for over 12 years. Several trees were brought down blocking roads in Curtin.

Other phenomena

There were 8thunderstorms (average 12) and 1 hail day (average 2) reported at Canberra Airport during summer. Storms occurred on 17, 18, 23 and 27 December; 7, 20 and 22 January and 23 February. The most significant storms were on 27 December (when up to 56 mm in some Canberra suburbs), 20 January (flash flooding in Curtin with 2cm hail) and 22 January (up to 38 mm in some suburbs). Hail was recorded at Canberra Airport on 20 January and a possible tornado in Canberra's northern suburbs on 22 January.

Canberra had a sunny summer with above average sunshine hours. The daily average for summer was 10.0 hours, well above the historic average of 9.3 hours. However, February was a partly cloudy month with below average sunshine (8.3 hours per day for that month).

Further information

NSW Climate Services Centre
NSW Regional Office
Bureau of Meteorology
Phone (02) 9296 1555
Email climate.nsw@bom.gov.au

Extremes for the ACT

Hottest day
Highest temperature
40.0°C at Canberra Airport on 7 and 8 Feb 2009
Warmest days on average
Highest mean daily maximum temperature
28.3°C at Canberra Airport
Coolest days on average
Lowest mean daily maximum temperature
28.3°C at Canberra Airport
19.1°C at Mount Ginini AWS
Coldest day
Lowest daily maximum temperature
6.0°C at Mount Ginini AWS on 12 Feb 2009
15.0°C at Tidbinbilla on 12 Feb 2009
15.8°C at Tuggeranong AWS on 12 Feb 2009
Coldest night
Lowest temperature
−1.0°C at Mount Ginini AWS on 20 Dec 2008
4.5°C at Tidbinbilla on 20 Dec 2008
5.6°C at Canberra Airport on 2 Dec 2008
Coolest nights on average
Lowest mean daily minimum temperature
8.2°C at Mount Ginini AWS
13.4°C at Canberra Airport
Warmest nights on average
Highest mean daily minimum temperature
13.7°C at Tuggeranong AWS
Warmest night
Highest daily minimum temperature
21.1°C at Tuggeranong AWS on 6 Feb 2009
and at Canberra Airport on 8 Feb 2009
Wettest overall
Highest total rainfall
241.2 mm at Curtin (Deakin West)
213.4 mm at Corin Dam
202.2 mm at Sullivan Creek (Southwell)
192.2 mm at Deakin
Driest overall
Lowest total rainfall
139.2 mm at Kingston
142.0 mm at Cook (Springvale Drive)
Wettest day
Highest daily rainfall
72.2 mm at Corin Forest on 13 Dec 2008
69.8 mm at Bendora Dam on 13 Dec 2008
67.2 mm at Curtin (Deakin West) on 13 Dec 2008
Highest wind gust
106 km/h at Canberra Airport on 20 Jan 2009

Records

Nil recorded

Summaries for the ACT

This table is very wide and may not fit if printed.

Summary statistics for summer 2008−09
Maximum temperatures
for summer 2008−09(°C)
Minimum temperatures
for summer 2008−09(°C)
Rainfall
for summer 2008−09(millimetres)
Mean for
summer
2008−09
Diff
from
average
Highest for
summer
2008−09
Mean for
summer
2008−09
Diff
from
average
Lowest for
summer
2008−09
Total for
summer
2008−09
Average
for
summer
Rank of
summer
2008−09
Fraction of
summer
average
Canberra Airport 28.3 +1.2 40.0 8 Feb 2009 13.4 +0.9 5.6 2 Dec 2008 179.2 167.3 average 107%
Tuggeranong 28.4 +0.1 39.9 8 Feb 2009 13.7 +0.3 5.7 2 Dec 2008 168.2
Mount Ginini AWS 19.1   29.0 8 Feb 2009 8.2   −1.0 20 Dec 2008 197.0

Notes

This statement has been prepared based on information available at 10am on Monday 2 March 2009. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Averages are long-term means based on observations from all available years of record, which vary widely from site to site. They are not shown for sites with less than 10 years of record, as they cannot then be calculated reliably.
The median is sometimes more representative than the mean of long-term average rain.

The Rank indicates how rainfall this time compares with the climate record for the site, based on the decile ranking (very low rainfall is in decile 1, low in decile 2 or 3, average in decile 4 to 7, high in decile 8 or 9 and very high is in decile 10).
The Fraction of average shows how much rain has fallen this time as a percentage of the long-term mean.

Further information

NSW Climate Services Centre
NSW Regional Office
Bureau of Meteorology
Phone (02) 9296 1555
Email climate.nsw@bom.gov.au