Tuesday 1 August 2006

A.C.T. MONTHLY CLIMATE SUMMARY - CANBERRA METEOROLOGICAL OFFICE

Canberra has warmer and drier July

July 2006 - Main Points:

• Warmer days and nights.
• Wamest average minimum temperature since 1988.
• Slightly drier than average.

Temperatures: Canberra has experienced significantly above average temperatures.   The average monthly mean temperature (the average of daytime and night-time temperatures) of 7.3 °C was 1.9°C above the historic average¹of 5.4°C,  Days were mild to cool with the average maximum day-time temperature of 12.7 °C being above the historic average of 11.2°C.

Nights were warmer overall with an average minimum temperature at Canberra Airport of 1.8°C, about two degrees above the historic average (of -0.4 °C) and the highest since 1988 when it was 2.1°C. Frosts (minimum temperature 2°C or less) were less common, Canberra Airport recording 16 frosts, 5 less than the historic average. The lowest temperature recorded at Tuggeranong was –6.2°C on the 8th.

Rainfall:   Canberra Airport's total July rainfall of 36.4mm was slightly below the historic average¹ of 41.7mm . The heaviest fall was on 15th when 11.0mm. There were 15 rain days during the month (historic average 9 days). Rainfall across the ACT ranged from 109.6mm at Tidbinbilla to 36.4mm at Canberra Airport.

Other phenomena:  There were 8 fog days compared to an historic average of 7 days. It was less windy than usual during July with a wind run of 159km/day (historic average 182km/day) with 2 strong wind days (historic average 2 days).

Canberra Airport  (Elev 578m)

July 2006

Historic average¹

July 2005

Average maximum
temperature (°C)

 12.7

11.2

12.7

Average minimum
temperature (°C)

1.8

-0.4

1.4

Mean temperature (°C)

7.3

5.4

7.1

Monthly rainfall (mm)

36.4

41.7

86.4

Number of rain days

15

9

10

Average daily
sunshine (hours)

5.7

5.7

6.3

Average relative humidity at 3pm (%)

59

58

60

Number of thunderstorms

0

0

0

Number of windy days*

 2

2

0

July 2006

All years

July 2006

All years *

July 2006

 15.5
(26th)

 19.7
(1957)

 15.6
 (4th)

  18.1  (2005)

7.0
   (27th)

 –5.8   (13th)

  –10.0  (1971)

-6.2
(8th)

  -7.5  (2002)

 –5.0



 (9th,13th,14th

& 20th)

8.8


 (24th)

   2.5 (1949)

8.6 

(24th)

   5.7  (2001)

  -1.0
 (9th)

 11.0  (15th)

  43.8 (1991)

15.8
(16th)

51.0
(2005)

 26.0
 (16th)

S @ 57  (18th)

W @ 105  (1990)

SSE @ 61  (18th)

-

-

This statement has been prepared based on information available at noon on 01/08/06. Although every effort has been made to check them, it is possible that results 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.  Rainfall averages & Extremes are based on all years 1939 - 2005.

Further information: Contact Owen Offler 02 6247 0411, 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 New South Wales localities are available here