ACT Monthly Climate Summary: October 2006
Warmest and sunniest October on record in Canberra

Wednesday 1 November, 2006

In Brief

October 2006 - Main Points:

  • Average maximum temperature of 24.2°C was highest on record (5°C above average).
  • Very warm days and cool nights.
  • Total rain 4 mm driest for October since 1977 and second driest on record.
  • Average daily sunshine highest on record at 10.9 hrs/day.
  • Very dry conditions with record low humidity and record high evaporation.

October 2006

Temperatures:    The October average monthly temperature (the average of daytime and night-time temperatures) of 14.9°C was the warmest on record (previous highest 14.4°C in 1991,1980 and 1944). The average maximum temperature at Canberra Airport was a very warm 24.2°C, which is significantly above the historic average1 of 19.2°C.  It is the warmest on record and easily exceeds the previous record of 22.4°C set in 1940.  There were 13 days with a maximum temperature of  25°C or more which is also a record (previous highest was 11 days in 1944).  The warmer than average conditions are consistent with global rising temperatures and enhanced by the current El Niño) event.

Nights were generally cool at Canberra Airport, the average minimum temperature of 5.5°C was slightly below the historic average1 of 6.0°C.

The highest temperature at Canberra Airport during October was 32.1°C on the 13th which is the second highest temperature on record for October (highest was 32.7°C in 1946).  The significant hot spell from 12th to 14th was unprecedented in October with Canberra experiencing 3 consecutive days of 30°C or more, the highest ever recorded in October.  The previous record was 2 days (12th and 13th in 1946). The lowest temperature was −1.2°C on the 22nd.  Corresponding temperature extremes at Tuggeranong ranged from a high of 31.8°C on the 13th to a low of 0.0°C on the 10th.

Rainfall:    The monthly rainfall total of 4.0 mm at Canberra Airport was the second driest October ever recorded and well below the historic October average of 64.2 mm.  It was the driest October since 1977 (when 2.4 mm was recorded, the driest on record).   There were 3 rain days, well below the average of 10 rain days.  A.C.T. rainfall totals ranged from 8.0 mm at Tharwa to 2.8 mm at Bruce AIS.  The very dry weather is consistent with El Niño) events and persistent high pressure systems over the Canberra area.

Other phenomena:   Canberra had plentiful sunshine during October with an average of 10.9 hours per day, the highest ever recorded in October.  The previous highest was 10.0 hrs per day in 1988 (historic average 8.5 hrs/day, records since 1978).  There were 2 thunderstorms (average 2) and 10 frosts during the month (historic average 6 frosts).  Canberra Airport reported 1 fog (average 2).  It was a little less windy than usual with an average wind run of 204 km per day (historic average 216 km/day), however there were 7 strong wind days (average 3).  Air pressure was well above average at 1020.9 hPa (historic average 1015.2 hPa) indicative of the persistence of high pressure systems over Canberra and southern NSW during October.  Very low humidity was recorded in Canberra during the month with an average at 3pm of 23% being the lowest ever recorded in October. Consistant with dry air was the record high evaporation of 237.6 mm, well above the October average of 157.1 mm (previous highest 213.9 mm in 1988).


Climate summary for Canberra Airport, October 2006

 

Canberra Airport  (Elev 578 m)

 

October 2006

Historic average1

October 2005

Average maximum
temperature (°C)

24.2

 19.2

 20.3

Average minimum
temperature (°C)

5.5

 6.0

 8.1

Mean temperature (°C)

14.9

 12.6

 14.2

Monthly rainfall (mm)

 4.0

64.2#

 61.0

Number of rain days

 3

 10

 14

Average daily
sunshine (hours)

 10.9

 8.5

 8.4

Average relative humidity at 3pm (%)

 23

 47

 49

Number of thunderstorms

 2

 2

 3

Number of windy days*

 7

 3

 3

Number of frosts

 10

6

2

# Median October rainfall is 56.5 mm.

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

Climate summary for Tuggeranong, October 2006

 

Tuggeranong  (Elev 587 m)

 

October 2006

Historic average #

October 2005

Average maximum
temperature (°C)

24.0

 20.0

 20.4

Average minimum
temperature (°C)

 5.3

 6.1

 7.6

Mean temperature (°C)

 14.7

 13.1

 14.0

Monthly rainfall (mm)

 5.6

 56.4

 54.6

Number of rain days

 2

 9

 13

# new station, historic average based on period 1996 - 2005.

Climate averages for Canberra are available, here.

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

 

Canberra Airport
 
(Elev 578 m)

Tuggeranong
 
(Elev 587 m)

Mount Ginini
 (Elev 1760 m)

 

October 2006

All years

October 2006

All years #

October 2006+

All years*

Highest temperature (°C) and date
Warmest day

32.1
13th

 32.7
(1946)

31.8
13th

31.2
(1997)

 20.0
(7th &12th)

20.3
(2004)

Lowest temperature (°C) and date
Coldest night

 −1.2
22nd

−3.3
(1957)

 0.0
10th

−2.3
(2001)

 −4.0
(9th & 28th)

−3.7
(2004)

Lowest maximum temperature (°C) and date
Coldest day

 13.6
21st

7.2
(1967)

13.5
21st

11.0
(1998)

 11.0
(9th,22nd,29th)

3.0
(2005)

Wettest 24hours (mm) and date

 2.2
19th

104.9
(1959)

 4.8
25th

60.0
(2000)

 8.0
(18th)

24.0
(2005)

Maximum Wind Gust (km/h) and date

 WNW
@ 78
18th

W
@ 121
(1980)

 WNW
@65
5th

 WNW
@ 65
(2006)

 n/a

  NW
@ 74
(2004)

  # new station, extremes based on period 1996 - 2006.   * new station, extremes based on period 2004 - 2006 only.

+ some days have incomplete data

This statement has been prepared based on information available at noon on 01/11/06. Although every effort has been made to check the data, it is possible that results in October 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 - 2005.

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