Thursday 1st March 2007 CANBERRA AIRPORT MONTHLY CLIMATE SUMMARY Record Stormy February in Canberra February 2007 - Main Points: Record number of thunderstorms. Total rainfall of 95.2 mm first above average monthly rainfall since June 2006. Large variability of rainfall totals throughout the ACT. Well above average temperatures. 14 hot days exceeding 30°C February 2007 Temperatures: February was the 8th consecutive month with an above average monthly temperature (the average of daytime and night-time temperatures) with 22.1°C, well above the historic average of 20.1°C . The average maximum temperature at Canberra Airport was a very warm 29.0°C also well above the historic average of 27.3°C. There were 14 days with a maximum temperature of 30°C or more which is substantially more than the average of 8 days. Canberra experienced very mild nights, the average minimum temperature of 15.2°C was the warmest February since 2003 when 15.4°C was recorded and well above the historic average¹of 13.0°C. The highest temperature at Canberra Airport during February was 34.9°C on the 5th . The lowest temperature was 11.3 °C on the 13th. Corresponding temperature extremes at Tuggeranong ranged from a high of 34.1°C on the 5th to a low of 11.1°C on the 17th. Rainfall: Canberra Airport received the majority of its monthly rainfall total of 95.2 mm from shower and storm activity and it was the first month since June 2006 (when 74.0mm) to have an above average monthly total. There were 11 rain days, well above the average of 6 rain days. Due to the thunderstorm and shower activity during February, the A.C.T. experienced a large variation in monthly rainfall totals ranging from 32.0 mm at Hall to 165.8 mm at Kambah and 151.4 mm at Torrens. Many of the storms caused flash flooding and damage to property. Other phenomena: Canberra Airport has experienced its stormiest month on record with 14 thunderstorms during February, well above the historic average of 3 storms. The previous highest was 12 thunderstorms in January 1999. The stormy conditions were due mainly to the persistence of a trough of low pressure over south-east NSW. Some storms were severe with flash flooding in the Kambah and Weston Creek areas on the 10th and 23rd and in Torrens also on the 23rd. The central city area of Canberra was hit by a severe hailstorm on the evening of the 27th, where flooding was associated with large amounts of hail, in some places to a depth of about half a metre and varying in size from 2cm to 5cm. Many businesses were closed due to damage from the hail and flash flooding. Hail was recorded on 1 day during the month (average 0). Average sunshine for February was 8.7 hours per day, slightly below the historic average of 9.0 hours per day. The wind run was 178 km per day, close to the historic average wind run of 179 km per day; and there were 2 strong wind days (average 1). Air pressure was above average at 1016.3 hPa (historic average 1013.9 hPa). The total evaporation of 203.6 mm was close to the historic average evaporation of 202.0 mm.

Thursday 1st March 2007

CANBERRA AIRPORT MONTHLY CLIMATE SUMMARY

Record Stormy February in Canberra

February 2007 - Main Points:

Record number of thunderstorms.
Total rainfall of 95.2 mm first above average monthly rainfall since June 2006.
Large variability of rainfall totals throughout the ACT.
Well above average temperatures.
14 hot days exceeding 30°C

February 2007

Temperatures: February was the 8th consecutive month with an above average monthly temperature (the average of daytime and night-time temperatures) with 22.1°C, well above the historic average of 20.1°C . The average maximum temperature at Canberra Airport was a very warm 29.0°C also well above the historic average of 27.3°C. There were 14 days with a maximum temperature of 30°C or more which is substantially more than the average of 8 days. Canberra experienced very mild nights, the average minimum temperature of 15.2°C was the warmest February since 2003 when 15.4°C was recorded and well above the historic average¹of 13.0°C.

The highest temperature at Canberra Airport during February was 34.9°C on the 5th . The lowest temperature was 11.3 °C on the 13th. Corresponding temperature extremes at Tuggeranong ranged from a high of 34.1°C on the 5th to a low of 11.1°C on the 17th.

Rainfall: Canberra Airport received the majority of its monthly rainfall total of 95.2 mm from shower and storm activity and it was the first month since June 2006 (when 74.0mm) to have an above average monthly total. There were 11 rain days, well above the average of 6 rain days. Due to the thunderstorm and shower activity during February, the A.C.T. experienced a large variation in monthly rainfall totals ranging from 32.0 mm at Hall to 165.8 mm at Kambah and 151.4 mm at Torrens. Many of the storms caused flash flooding and damage to property.

Other phenomena: Canberra Airport has experienced its stormiest month on record with 14 thunderstorms during February, well above the historic average of 3 storms. The previous highest was 12 thunderstorms in January 1999. The stormy conditions were due mainly to the persistence of a trough of low pressure over south-east NSW. Some storms were severe with flash flooding in the Kambah and Weston Creek areas on the 10th and 23rd and in Torrens also on the 23rd. The central city area of Canberra was hit by a severe hailstorm on the evening of the 27th, where flooding was associated with large amounts of hail, in some places to a depth of about half a metre and varying in size from 2cm to 5cm. Many businesses were closed due to damage from the hail and flash flooding.

Hail was recorded on 1 day during the month (average 0). Average sunshine for February was 8.7 hours per day, slightly below the historic average of 9.0 hours per day. The wind run was 178 km per day, close to the historic average wind run of 179 km per day; and there were 2 strong wind days (average 1). Air pressure was above average at 1016.3 hPa (historic average 1013.9 hPa). The total evaporation of 203.6 mm was close to the historic average evaporation of 202.0 mm.

Climate summary for Canberra Airport, February 2007

	Canberra Airport (Elev 578m)
	February 2007	Historic average¹	February 2006
Average maximum temperature (°C)	29.0	27.3	30.5
Average minimum temperature (°C)	15.2	13.0	14.8
Mean temperature (°C)	22.1	20.1	22.7
Monthly rainfall (mm)	95.2	55.4#	23.6
Number of rain days	11	7	3
Average daily sunshine (hours)	8.7	9.0	10.9
Average relative humidity at 3pm (%)	39	40	32
Number of thunderstorms	14	3	2
Number of windy days*	2	1	1
Number of frosts	0	0	0

# Median February rainfall is 47.7mm.

* windy day defined as average wind speed of 40 km/h or more.

Climate summary for Tuggeranong, February 2007

	Tuggeranong (Elev 587m)
	February 2007	Historic average #	February 2006
Average maximum temperature (°C)	28.3	28.8	30.5
Average minimum temperature (°C)	15.2	14.2	15.2
Mean temperature (°C)	21.7	21.5	22.8
Monthly rainfall (mm)	101.8	61.2	47.2
Number of rain days	12	11	3

# new station, historic average based on period 1996 - 2006.

Climate averages for Canberra are available, here.

Daily Extremes for February for the A.C.T.

	Canberra Airport (Elev 578m)		Tuggeranong (Elev 587m)
	February 2007	All years	February 2007	All years #
Highest temperature (°C) and date Warmest day	34.9 5th	42.2 (1968)	34.1 5th	39.8 (2004)
Lowest temperature (°C) and date Coldest night	11.3 13th	3.0 (1985)	11.1 17th	5.3 (1998)
Lowest maximum temperature (°C) and date Coldest day	21.9 11th	12.0 (1949)	21.1 11th	12.7 (2005)
Wettest 24hours (mm) and date	39.0 28th	77.8 (2002)	26.2 3rd	80.0 (2001
Maximum Wind Gust (km/h) and date	NE @ 72 10th	WNW @ 104 (1940)	S @52 24th	NW @ 61 (2006)

# new station, extremes based on period 1996 - 2006.

This statement has been prepared based on information available at noon on 01/03/2007. Although every effort has been made to check the data, it is possible that results for February may change as new information becomes available.

A note about deciles: Deciles are used to give an element (in this case rainfall or temperature) a ranking. Deciles are calculated by arranging the totals in ascending order (from lowest to highest) then splitting them into 10 equal groups (thus the groups are called deciles). The first group would be in decile range one, the second group in decile range two, etc up to the highest annual totals (highest 10 per cent) being in decile range 10.

¹Averages: Historic average temperatures for Canberra Airport are based on the period 1961 to 1990 which is a convention of the World Meteorological Organisation. Historic rainfall averages and extremes for Canberra Airport are based on all years of record 1939 - 2006.

Further information: Contact: Owen Offler on 02 62470411 or email: climate.act@bom.gov.au

A directory of Bureau services is available on poll fax: 1800 630 100

The latest rainfall and temperature maps are available here
Climate averages for New South Wales localities are available here
Daily Weather Observations for selected Australian Capital Territory localities are available here