Friday, 31 July 2009 - Monthly Climate Summary for Brisbane Metro - Product code IDCKGC24R0

Brisbane Metro in July 2009

  • Dry month for the metropolitan area
  • Maximum temperatures within a degree of the long term average.
  • Minimum temperatures within, or just above the long term average.

Based on preliminary data

This statement was prepared before all data for the period were available. This may affect some of the statistics presented. In particular, maximum temperatures for the final day were not available, as the “accounting period” had not finished. Final values, which have had greater opportunity for data quality control, will be presented in the Monthly Weather Review, which is usually published during the fourth week of the month.

An archive of previous monthly summaries for Brisbane Metro is also available, as are summaries for other states and many other climate summaries and diagnostics.

Details

Dry over the metropolitan area for the month of July, where monthly totals did not exceed 5 mm.  Both maximum and minimum temperatures were within a degree of the long term average. However, some individual warm days were observed, as well as very cool nights.

Rainfall

Very little rain fell over the metropolitan area during July. Statistically, this is one of the driest months of the year, with around 50 mm of rain on average expected to fall.  However, the metropolitan sites recorded around 10% or less of their average rainfall.

The wettest overall was 4.6 mm at Logan City Water Treatment, then 4.0 mm at Redcliffe and finally 3.6 mm at Brisbane.

Widespread, but relatively light falls were recorded over the southeast corner of the state on the afternoon of the 7th. As a result, the highest daily rainfall for the metropolitan area for July was 3.6 mm at Logan City Water Treatment, followed by 3.4 mm at both Brisbane and Redcliffe, all recorded to 9am on the 8th.

Maximum temperature

Daytime temperatures were within a degree of the long term average at the metropolitan sites. The average maximum temperature across the metropolitan area falls into the range of 20C to 21.5 C for July.

The hottest day was on the 23rd, with 26.5 C recorded at Logan City Water Treatment, 26.3 C at Redcliffe and 26.2 C at Amberley. Light to moderate northeast to northwest winds brought these warmer conditions to the southeast. A daily maximum temperature anomaly map illustrates this.

Minimum temperature

Overnight temperatures were within, or just above a degree of the long term average at the metropolitan sites.

The coldest night was recorded at Amberley on the 15th, with 0.3 C. Cool and dry southwest winds were observed throughout the state on the 15th, and these anomalies can be seen on the minimum temperature anomaly map.

Wind

The strongest wind gust was on the 3rd, with 69 km/h recorded at Brisbane Aero and 63 km/h at Archerfield Airport.

Further information

Queensland Climate Services Centre
Bureau of Meteorology
Phone (07) 3239 8700
Email climate.qld@bom.gov.au

Extremes

Hottest day
Highest temperature
26.5 C at Logan City Water Treatment on the 23rd
Warmest days on average
Highest mean daily maximum temperature
21.6 C at Amberley AMO
Coolest days on average
Lowest mean daily maximum temperature
20.3 C at Redcliffe
Coldest day
Lowest daily maximum temperature
15.6 C at Amberley AMO on the 7th
Coldest night
Lowest temperature
0.3 C at Amberley AMO on the 15th
Coolest nights on average
Lowest mean daily minimum temperature
4.8 C at Amberley AMO
Warmest nights on average
Highest mean daily minimum temperature
10.5 C at Redcliffe
Warmest night
Highest daily minimum temperature
15.2 C at Redcliffe on the 23rd
Wettest overall
Highest total rainfall
4.6 mm at Logan City Water Treatment
Wettest day
Highest daily rainfall
3.6 mm at Logan City Water Treatment on the 8th
Highest wind gust
69 km/h at Brisbane Aero on the 3rd

Summaries

This table is very wide and may not fit if printed.

Summary statistics for July 2009
Maximum temperatures
for July
(C)
Minimum temperatures
for July
(C)
Rainfall
for July
(millimetres)
Mean for
July
2009
Diff
from
average
Highest for
July
2009
Mean for
July
2009
Diff
from
average
Lowest for
July
2009
Total for
July
2009
Average
for
July
Rank of
July
2009
Fraction of
July
average
Moreton South Coast (district 40)
Amberley AMO 21.6 +0.4 26.2 23rd 4.8 -0.5 0.3 15th 2.6 39.5 very low 7%
Archerfield Airport 21.2 +0.1 25.7 23rd 7.5 0.0 3.0 15th 2.2 49.7 very low 4%
Brisbane* 21.4  +1.0 25.8 23rd 10.2 +0.7 6.2 15th 3.6 56.5 very low 6%
Brisbane Aero* 20.8 +0.2 25.3 13th 8.8 -0.7 3.7 15th 3.0 62.6 very low 5%
Logan City Water Treatment 21.4 0.0 26.5 23rd 9.7 +1.2 6.0 15th 4.6 35.6 low 13%
Redcliffe* 20.3 -0.4 26.3 23rd 10.5 +0.6 6.3  5th 4.0 51.3 very low 8%

Notes

This statement has been prepared based on information available at 12 pm on Friday 31 July 2009. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Averages are long term means based on observations from all available years of record, which vary widely from site to site. They are not shown for sites with less than 10 years of record, as they cannot then be calculated reliably. *In this case, averages from a nearby suitable site have been used instead (these are marked with an *). 

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.