Thursday, 1 November 2007 - Monthly Climate Summary for ACT Region - Product code IDCKGC1xx0

Record warm October for Canberra.

 

Summary

  • Well below average rainfall during October
  • Very warm day and night-time temperatures 

Rainfall

Canberra Airport recorded a total rainfall of 22.6 mm during October well below the historic average of 62.7 mm. Welcome showers and thunderstorms associated with the passage of several cold fronts and associated low pressure systems during the latter part of the month brought some relief from the dry conditons that had persisted during the earlier part of the month when the ACT remained under the influence of persistent high pressure systems. There were 7 rain days during October, compared to the average of 10 days. There was considerable variation in October rainfall totals across the ACT with totals ranging from 60.2 mm at Mount Ginini to 18.0 mm at Melba.

Temperature

Canberra Airport experienced a very warm month with the mean daily temperature (the average of the  mean maximum and  mean minimum temperatures) reaching 15.7 C, this is a new record (previous record was 14.9 C in 2006) and is significantly above the long term average of 12.7 C.  The average maximum (day-time) temperature during October was also a very warm 23.2 C this is 3.9 C above the long term average of 19.3 C and the second highest on record (the record is 24.2 C in 2006). Most days during the month recording above average maximum temperatures (apart from 2 days), there were also 2 days where the maiximum temperature was greater than 30 C. Canberra Airport also experienced very warm average minimum (night-time) temperatures during October, the average minimum of  8.2 C being 2.2 C above the historic average of 6.0 C and the warmest for 34 years (9.0 C in 1973).

Extremes of temperature at Canberra Airport ranged from a high of 30.8 C on the 21st to a low of 0.4 C on the 13th. Corresponding extremes for Tuggeranong ranged from a high of  31.1C on the 21st to a low of -0.7 C on the 13th. 

Other phenomena

Canberra Airport recorded 4 frosts compared to the long term average of 6 frosts. There were no fogs (average 2 fogs).  It was generally a very sunny month with sunshine averaging 10.1 hours per day (long term average 8.6 hours per day).  October was also a very windy month with an average wind run of  236km per day compared to the long term average of 216 km per day. There were 5 strong wind days (average 3) and 1 gale day (average 0) on the 3rd when tree damage was reported in several ACT suburbs.

There were 4 thunderstorms (average 2) and 1 hail day (on the 26th) reported a Canberra Airport.  The average air pressure of 1013.9 hPA was slightly below the long term average of 1015.3 hPa. Due to the very warm temperatures and windy conditions during October, Canberra Airport has recorded the second highest evaporation reading on record for October with 231.2 mm (record is 238.7 mm in 2006) compared to the long term average of 159.1mm

Further information

Owen Offler
Climate Information Officer
Climate Services Centre
Canberra Meteorological Office
Bureau of Meteorology
Phone (02) 62470411
Email climate.act@bom.gov.au

Extremes

Hottest day
Highest temperature
31.1 C at Tuggeranong (Isabella Plains) AWS on the 21st
Warmest days on average
Highest mean daily maximum temperature
23.2 C at Canberra Airport
Coolest days on average
Lowest mean daily maximum temperature
23.0 C at Tuggeranong (Isabella Plains) AWS
Coldest day
Lowest daily maximum temperature
18.4 C at Canberra Airport on the 13th
Coldest night
Lowest temperature
-0.7 C at Tuggeranong (Isabella Plains) AWS on the 13th
Coolest nights on average
Lowest mean daily minimum temperature
7.6 C at Tuggeranong (Isabella Plains) AWS
Warmest nights on average
Highest mean daily minimum temperature
8.2 C at Canberra Airport
Warmest night
Highest daily minimum temperature
15.5 C at Canberra Airport on the 16th
Wettest overall
Highest total rainfall
60.2 mm at Mt Ginini AWS
Driest overall
Lowest total rainfall
18.0 mm at Melba
Wettest day
Highest daily rainfall
18.0 mm at Tuggeranong (Isabella Plains) AWS on the 26th
Highest wind gust
94 km/h at Canberra Airport on the 3rd

 

Summaries

In this table, key sites have been highlighted to make them easier to find. This table is very wide and may not fit if printed.

Summary statistics for October 2007
Maximum temperatures
for October
(C)
Minimum temperatures
for October
(C)
Rainfall
for October
(millimetres)
Mean for
October
2007
Diff
from
normal
Highest for
October
2007
Mean for
October
2007
Diff
from
normal
Lowest for
October
2007
Total for
October
2007
Normal
for
October
Rank of
October
2007
Fraction of
October
normal
Sthn Tablelands Gburn-Monaro (district 70)
Canberra Airport 23.2 +3.9 30.8 21st 8.2 +2.2 0.4 13th 22.6 62.7 low 36%
Tuggeranong 23.0 +2.7 31.1 21st 7.6 +1.5 -0.7 13th 36.4 50.5 low 72%

Notes

This statement has been prepared based on information available at midday on Thursday, 1 November 2007. Some checks have been made on the data, but it is possible that results will 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. Normals are long-term averages based on observations from all available years of record, which vary from site to site. They are not shown for sites with less than 20 years of record for temperature and less than 30 years of record for rainfall, as they cannot then be calculated reliably.

Further information

Owen Offler
Climate Information Officer
Climate Services Centre
Canberra Meteorological Office
Bureau of Meteorology
Phone (02)62470411
Email climate.act@bom.gov.au