Thursday, 3 December 2009 - Seasonal Climate Summary for ACT Monthly Summary - Product code IDCKGC25R0

Record heat for Canberra during spring

  • Warmest spring on record for minimum (night-time) temperatures
  • Equal 5th warmest spring on record for maximum (day-time) temperatures
  • Below average rainfall

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

Details Extremes Maps Records Summaries Important notes the top

Rainfall

Canberra Airport recorded a total rainfall of 117.8 mm in spring, which is below the historical average1of 178.2 mm. This is the lowest spring rainfall for Canberra Airport since 2006 (64.2 mm), and the 5th consecutive spring with below average rainfall. Much of the rain fell September and October, associated with thunderstorm activity, particularly on the 23rd September (27.2 mm) and the 26th October (14.2 mm). There were 31 rain days, which is normal for spring.

Spring rainfall across the ACT was highest in the ranges southwest of Canberra, where Corin Dam recorded 340.8 mm. The highest in suburban Canberra was 181.7 mm at Nicholls (northern suburbs) while the lowest total was 115.6 mm at Cook (Belconnen).

See a map of rainfall deciles.

Temperatures

It was the warmest spring on record at Canberra Airport for overnight minimum temperatures. The mean minimum temperature was 7.9 °C, which is 1.9 °C above the historical1 spring average. Canberra Airport has now experienced 15 consecutive springs with above average mean minimum temperatures. There were 6 days in spring with a minimum temperature of 15 °C or higher at Canberra Airport, above the historical spring average of 2.

The spring average maximum temperature at Canberra Airport 21.8 °C, which is 2.4 °C above the historical spring average. This is the equal 5th warmest spring on record for mean maximum temperatures, and the 6th consecutive spring with above average mean maximum temperatures. In addition to the warm mean temperature, Canberra Airport recorded its highest spring temperature on record of 38.9 °C on the 20th November. There were 15 days above 30 °C during spring at Canberra Airport (historical average 3 days) and 3 days above 35 °C (historical average once in every 5 years).

Canberra Airport experienced above average maximum and minimum temperatures throughout each month of spring, however the standout month was November, where both day-time and night-time temperatures were the warmest on record. Refer to the November ACT climate summary for further information.

Similar high temperatures were experienced through much of New South Wales and the ACT region. The high temperatures were mostly a result of a persistent high pressure system in the Tasman Sea, which restricted the passage of any significant cool systems and directed warm northwesterly airstream over the region. In addition, an El Niño event has matured in the equatorial Pacific Ocean. These events are usually (but not always) associated with above average temperatures in eastern Australia. The recent high temperatures experienced are likely due to the current influence of El Niño combined with the background, long-term warming that has been observed across Australia since the start of last century.

The highest temperature in the ACT during spring was 38.9 °C at Canberra Airport on the 20th November, while the lowest temperature was -6.1 °C at Mount Ginini AWS on the 27th September. The lowest temperature in suburban Canberra was -2.5 °C at Tuggeranong AWS on 6th September.

See a map of maximum temperature anomalies. See a map of minimum temperature anomalies.

Wind

During spring the prevailing wind at Canberra Airport was from the west-northwest. During the mornings (9am) the wind was from the W-NW 35% of the time. In the afternoons (3pm) the wind was W-NW for 49% of the time. Eight strong wind days were reported during spring at Canberra Airport (average 3 strong wind days), with the majority reported in November (4). The highest wind gust recorded at Canberra Airport was 80 km/h on the 3rd November, and the highest in the ACT was 113 km/h at Mount Ginini AWS on the 25th September.

Other phenomena

Eleven thunderstorms were observed at Canberra Airport during spring (average 8) with no hail days. Bright sunshine averaged 8.1 hours per day which is normal for spring. There were 10 frosts, well below the spring average of 22, and 6 fogs, close to the average of 8. No official reports of snow occurred at Canberra Airport during spring, although sleet was recorded in some Canberra suburbs on 27th September and snowfalls on the ACT ranges southwest of Canberra on 26th and 27th September and 7th and 14th October. A duststorm affected Canberra and the ACT on 22nd September reducing visibility to 3000 metres for much of the day.

Further information

NSW Climate Services Centre
NSW Regional Office
Bureau of Meteorology
Phone (02) 9296 1555
Email climate.nsw@bom.gov.au
Extremes in spring 2009
Hottest day 38.9 °C at Canberra Airport on 20 Nov
Warmest days on average 21.8 °C at Canberra Airport
Coolest days on average 21.7 °C at Tuggeranong AWS
Coldest day 9.0 °C at Canberra Airport on 27 Sep
-2.5 °C at Mount Ginini AWS on 26 Sep
Coldest night -2.5 °C at Tuggeranong AWS on 6th Sep
-6.1 °C at Mount Ginini AWS on 27 Sep
Coolest nights on average 7.7 °C at Tuggeranong AWS
Warmest nights on average 7.9 °C at Canberra Airport
Warmest night 19.1 °C at Tuggeranong AWS on 21 Nov
Wettest overall 340.8 mm at Corin Dam
181.7 mm at Nicholls (Gungahlin Lakes)
Driest overall 115.6 mm at Cook (Belconnen)
Wettest day 51.4 mm at Nicholls (Gungahlin Lakes) on 23 Sep
Highest wind gust 113 km/h at Mount Ginini AWS* on 25 Sep
80 km/h at Canberra Airport on 3 Nov

*Incomplete data record.

Details Extremes Maps Records Summaries Important notes the top

Record highest spring temperature
Highest temperature
in spring 2009 (°C) 		Previous highest
for spring		 Years of
record		 Average for
spring
Canberra Airport 38.9 on 20 Nov = 38.9 on 26 Nov 1997 71 19.4


Record highest spring mean daily minimum temperature
Mean daily minimum
temperature
for spring 2009 (°C) 		Previous highest
for spring		 Years of
record		 Average for
spring
Canberra Airport 7.9 7.8 in 2007 70 6.0


Details Extremes Maps Records Summaries Important notes the top

Summary statistics for spring 2009
Maximum temperatures
for spring
(°C)		 Minimum temperatures
for spring
(°C)		 Rainfall
for spring
(millimetres)
Mean for
spring
2009		 Diff
from
average		 Highest for
spring
2009		 Mean for
spring
2009		 Diff
from
average		 Lowest for
spring
2009		 Total for
spring
2009		 Average
for
spring		 Rank of
spring
2009		 Fraction of
spring
average
Southern Tablelands
Canberra Airport 21.8 +2.4 38.9 20 Nov 7.9 +1.9 -2.3 6 Sep 117.8 178.2 low 66%
Mount Ginini AWS* 12.4   27.8 20 Nov 3.5   -6.1 27 Sep 316.4
Tidbinbilla * 20.8 +2.0 36.5 20 Nov 6.6 +0.4 -3.5 2 Sep 189.9 261.0 average 73%
Tuggeranong AWS** 21.7 +1.1 37.9 20 Nov 7.7 +1.1 -2.5 6 Sep 153.6

* Incomplete data record.
** Historic average temperature based on short period of record only, 1996-2009. No rainfall averages available.

Details Extremes Maps Records Summaries Important notes the top

Notes

A Seasonal Climate Summary is prepared to list the main features of the weather in ACT Monthly Summary using the most timely and accurate information available on the date of publication; it will generally not be updated. Later information, including data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review, usually published in the fourth week of the month.

This statement has been prepared based on information available at 9 am on Thursday 3 December 2009. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

1Averages are long-term means based on observations from all available years of record, which vary widely from site to site.
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