Greater Melbourne in September 2018: drier than average with cool nights

September rainfall was very much below average throughout Greater Melbourne. Daytime temperatures in September were generally warmer than average, while nights were cooler than average.

Drier than average

  • September rainfall was below to very much below average at all sites across Greater Melbourne
  • In the city, Melbourne (Olympic Park) recorded 16.4 mm for the month, making it the city's fifth-driest September on record and the driest since 2008 when just 12.0 mm was recorded at the old Melbourne Regional Office site
  • Melbourne (Olympic Park) had no days during the month with a rainfall total of more than 5.0 mm, which is only the second time that has happened in September since rainfall records began in the city in 1855, and the first time since 1907
  • Monthly rainfall totals ranged from 24% of average at Laverton RAAF to 63% of average at Cerberus
  • Laverton RAAF had its lowest total September rainfall on record and several sites had their lowest total September rainfall since 1981

Cool nights, warm days

  • Daytime temperatures around Greater Melbourne were generally warmer than average during September
  • Melbourne's two warmest days for the month were on the 11th and 27th, when warm northerly winds ahead of cold fronts resulted in maximum temperatures in the mid-20s and the warmest days since autumn
  • The hottest temperature recorded in Greater Melbourne for the month was 25.3 °C at Laverton RAAF on the 27th
  • Mean maximum temperatures ranged from 0.3 °C cooler than average at Viewbank to 0.8 °C warmer than average at Essendon
  • Night time temperatures were cooler than average at all sites around Greater Melbourne
  • Mean minimum temperatures ranged from 2.6 °C cooler than average at Coldstream to 0.2 °C cooler than average at Essendon Airport
  • Coldstream had its lowest September mean daily minimum temperature on record and equalled its lowest September mean temperature on record, while Melbourne Airport had its lowest September mean daily minimum temperature since 1982

Melbourne (Olympic Park)

  • Total rainfall for Melbourne (Olympic Park) was 16.4 mm
  • The mean daily maximum temperature for Melbourne (Olympic Park) was 17.2 °C. The warmest day was 24.2 °C on the 27th, and the coolest day was on the 2nd when the temperature reached 12.3 °C
  • The mean daily minimum temperature for Melbourne (Olympic Park) was 8.1 °C. The coldest morning was 3.4 °C on the 4th, and the warmest morning was on the 6th when the minimum temperature was 13.8 °C

Strong winds at times

  • The strongest wind gust recorded in Greater Melbourne during September was 93 km/h at South Channel Island on the 11th
  • Associated with a cold front, numerous sites around Melbourne recorded gusts in excess of 80 km/h on the 15th
  • After two months of windy conditions in July and August, the total wind run at sites around Greater Melbourne for September was close to average

Further information

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Extremes in September 2018
Hottest day 25.3 °C at Laverton RAAF on the 27th
Warmest days on average 17.7 °C at Laverton RAAF
Coolest days on average 13.3 °C at Ferny Creek
Coldest day 8.6 °C at Ferny Creek on the 23rd
Coldest night -1.9 °C at Coldstream on the 3rd
Coolest nights on average 3.0 °C at Coldstream
Warmest nights on average 8.1 °C at Melbourne (Olympic Park)
Warmest night 13.8 °C at Melbourne (Olympic Park) on the 6th
Warmest on average overall 12.7 °C at Melbourne (Olympic Park)
Coolest on average overall 9.2 °C at Wallan (Kilmore Gap)
Wettest overall 52.8 mm at Toolangi (Mount St Leonard DPI)
Driest overall 11.8 mm at Laverton RAAF
Wettest day 25.2 mm at Toolangi (Mount St Leonard DPI) on the 7th
Strongest wind gust 93 km/h at South Channel Island on the 11th

Record lowest September total rainfall
New record
(mm)
Old
record
Years of
record
Average for
September
Laverton RAAF 11.8 14.4 in 1981 78 48.6

Lowest September total rainfall for at least 20 years
Observed
(mm)
Most recent
lower
Average for
September
Bullengarook East 27.2 26.2 in 1981* 78.0
Cheltenham Kingston Centre 18.4 15.8 in 1981* 65.8
Toolangi (Mount St Leonard DPI) 52.8 45.2 in 1981* 134.8
Woodend 26.2 23.8 in 1981* 82.2

* note: there are gaps in the historical record at this site, so it is possible a lower value has gone unreported




Record lowest September mean daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
September
Coldstream 3.0 3.9 in 2006 23 5.6

Lowest September mean daily minimum temperature for at least 20 years
Observed
(°C)
Most recent
lower
Average for
September
Melbourne Airport 5.7 5.4 in 1982 7.1



Record lowest September mean temperature
New record
(°C)
Old
record
Years of
record
Average for
September
Coldstream 10.1 = 10.1 in 2003 23 11.4



Summary statistics for September 2018
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
September
2018
Diff
from
average
Highest for
September
2018
Mean for
September
2018
Diff
from
average
Lowest for
September
2018
Total for
September
2018
Average
for
September
Rank of
September
2018
Fraction of
September
average
Cerberus 16.5 0.0 24.0 11th 6.8 -0.8 -0.2 4th 41.8 66.6 low 63%
Coldstream 17.1 -0.1 22.4 27th 3.0 -2.6 -1.9 3rd 23.4 68.3 v low 34%
Essendon Airport 17.6 +0.8 24.0 27th 6.6 -0.2 1.4 4th 14.6 50.9 v low 29%
Ferny Creek 13.3   19.6 27th 5.5   0.9 16th 42.8
Laverton RAAF 17.7 +0.7 25.3 27th 6.3 -0.4 0.8 4th 11.8 48.6 lowest 24%
Melbourne (Olympic Park) 17.2   24.2 27th 8.1   3.4 4th 16.4
Melbourne Airport 17.4 +0.7 24.3 27th 5.7 -1.4 1.7 4th 16.4 46.6 v low 35%
Moorabbin Airport 17.2 +0.3 24.6 27th 7.1 -1.0 1.7 24th 25.8 64.0 v low 40%
Scoresby Research Institute     24.1 27th     0.8 3rd 33.0 82.4 v low 40%
Viewbank 17.4 -0.3 24.6 27th 5.7 -2.1 0.5 4th 15.2 54.0 v low 28%
Wallan (Kilmore Gap) 13.5 +0.3 19.3 27th 4.9 -0.8 1.0 29th 17.8 60.7 v low 29%

Daily maximum temperatures for September 2018
123456789101112131415161718192021222324252627282930
Bundoora (Latrobe University)14.019.119.020.218.218.819.321.015.717.815.213.320.0
Cerberus12.912.613.017.419.720.614.215.717.417.224.016.618.922.212.613.817.918.814.316.516.413.414.913.217.423.814.313.214.6
Coldstream13.212.514.819.419.518.815.316.517.117.322.417.518.320.715.113.616.220.915.316.919.120.813.717.013.619.922.414.614.016.9
Cranbourne Botanic Gardens12.513.717.819.720.116.523.822.016.917.216.612.814.518.124.114.413.715.8
Essendon Airport15.812.613.519.519.820.114.517.218.517.723.718.719.822.914.414.418.320.216.817.819.319.213.515.615.119.324.015.914.016.9
Ferny Creek9.29.012.615.815.814.911.512.612.613.418.614.115.417.59.810.513.315.511.913.215.216.38.612.810.515.719.610.810.912.5
Laverton RAAF14.112.713.619.319.620.114.818.018.718.024.819.021.223.414.214.619.221.815.716.419.619.214.515.414.817.625.315.214.016.2
Melbourne (Olympic Park)13.412.313.119.520.220.615.117.518.118.024.218.519.722.713.714.018.120.314.717.418.917.313.714.913.617.624.215.214.016.5
Melbourne Airport15.212.713.918.719.219.514.417.318.418.023.718.119.722.813.413.818.121.415.417.718.820.212.915.314.619.024.315.214.416.6
Moorabbin Airport12.013.217.920.120.314.616.417.417.624.517.420.122.814.113.818.519.914.516.917.616.414.616.314.719.024.615.114.115.6
Scoresby Research Institute13.912.114.419.119.719.416.617.117.222.917.819.021.813.416.919.914.817.218.616.114.819.424.114.414.016.8
Viewbank13.811.914.719.419.119.515.016.918.017.523.118.618.921.814.413.917.820.414.818.219.520.013.616.614.319.624.615.314.917.1
Wallan (Kilmore Gap)11.88.710.814.414.614.411.613.114.414.418.814.314.417.810.210.913.517.411.214.315.118.08.811.910.015.919.313.610.312.5
Values are the maximum temperature, usually in the 24 hours from 9 am on the day indicated,
and typically occurred in the afternoon of that day.
Temperatures coloured according to their difference
from the long-term average for the period
-10.0 -9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0 +1.0 +2.0 +3.0 +4.0 +5.0 +6.0 +7.0 +8.0 +9.0 +10.0 °C Grey outline marks highest
and lowest for the period

Daily minimum temperatures for September 2018
123456789101112131415161718192021222324252627282930
Bundoora (Latrobe University)0.74.812.76.25.54.96.50.45.12.71.25.2
Cerberus9.44.64.5-0.26.610.88.32.49.711.35.310.35.17.89.55.24.39.67.53.16.24.18.94.79.65.88.95.67.1
Coldstream9.40.8-1.9-1.51.710.16.90.84.36.23.07.31.11.712.7-0.50.74.53.4-1.52.40.85.4-0.4-0.2-0.82.64.93.03.0
Cranbourne Botanic Gardens8.53.12.45.611.43.09.55.69.04.15.46.52.57.26.47.52.26.42.68.63.54.4
Essendon Airport9.53.22.71.46.611.77.02.810.311.88.19.05.79.010.63.64.110.06.63.76.65.09.64.48.62.66.27.24.05.5
Ferny Creek6.02.43.15.08.99.64.74.67.78.39.46.44.39.18.00.93.48.93.82.45.86.35.93.43.92.88.36.61.83.2
Laverton RAAF8.54.43.70.85.611.95.81.910.510.47.18.55.49.39.53.04.210.65.32.26.54.57.76.49.93.16.86.52.75.4
Melbourne (Olympic Park)10.55.05.03.48.113.88.74.28.613.49.111.77.110.910.25.56.711.08.53.88.36.810.44.68.66.49.210.75.56.8
Melbourne Airport7.63.52.71.75.39.05.83.28.69.69.57.45.56.59.93.04.28.44.92.35.94.88.83.46.82.86.86.43.14.2
Moorabbin Airport10.33.03.51.86.08.34.59.911.96.610.77.88.59.85.46.511.78.14.38.46.010.21.76.62.36.910.26.47.2
Scoresby Research Institute8.92.20.81.66.513.12.48.79.17.810.45.711.010.46.35.34.63.10.97.18.53.94.8
Viewbank9.71.71.10.55.613.77.31.15.811.95.610.33.15.910.73.63.210.47.90.75.43.79.72.54.51.46.58.63.74.0
Wallan (Kilmore Gap)5.92.01.93.27.68.34.44.05.58.27.25.85.46.09.11.32.45.03.63.86.36.76.42.04.02.26.76.51.04.2
Values are the minimum temperature, usually in the 24 hours to 9 am on the day indicated,
and typically occurred that morning.
Temperatures coloured according to their difference
from the long-term average for the period
-10.0 -9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0 +1.0 +2.0 +3.0 +4.0 +5.0 +6.0 +7.0 +8.0 +9.0 +10.0 °C Grey outline marks highest
and lowest for the period

Daily rainfall for September 2018
123456789101112131415161718192021222324252627282930
Bonbeach (Carrum) 7.0 - 2.0 - - - 12.5 - - - - - - - - 4.0 - - 5.4
Bullengarook East 1.4 2.4 0.2 0.2 0.2 1.2 3.4 0.2 - - - - - - 0.4 3.8 0.2 - 3.8 1.6 - - 0.6 6.2 0.4 - - 1.0 - -
Bundoora (Latrobe University) 8.6 - - - 1.0 - - - - - - - 3.6 - - 0.2 - 0.4 - - -


Burnside 0.6 3.0 - - - - 2.2 - - - - - - - - 1.0 - - - 4.8 - - 1.8 - - - - - 1.4 -
Cape Schanck 3.8 4.0 2.8 - - 3.8 10.8 - - - - - - - 0.8 10.8 0.8 - - - - - 3.2 - - - - 0.6 3.4 2.2
Cerberus 4.2 1.8 0.8 - - 1.0 6.0 - 0.2 - 0.2 - - - 1.4 10.6 0.4 - 2.0 - - - 1.6 0.2 - - - - 11.0 0.4
Cheltenham Kingston Centre 2.1 2.0 0.8 - - 0.5 1.8 - - - - - - - 0.2 2.8 - - 4.0 - - - 2.0 - - - - 2.2 -
Coldstream 5.6 0.8 0.6 - - - 6.8 0.2 - - - - - - - 4.0 - - - 0.2 - - - - 0.2 - - - 4.8 0.2
Cranbourne Botanic Gardens 5.2 0.4 0.8 - 1.3 6.2 - - - - - - 1.4 10.5 - 5.2 0.8 - - 2.0 0.6 - - - 0.4 6.0 4.4
Essendon Airport 1.4 3.0 - - - - 4.8 - - - - - - - - 1.2 - - 0.6 0.6 - - 0.8 - - - - - 2.2 -
Ferny Creek 7.8 1.2 2.2 - - 1.2 8.4 0.2 - 0.6 - - - - - 7.8 - - 0.6 - - - 3.0 0.2 - - - - 9.0 0.6
Greenvale Reservoir 2.8 5.8 0.2 0.2 -
2.0 -

- - -

1.8 -
0.8 2.6 - - 1.0
- -
-
0.2
Kinglake West 1.4 8.0 1.0 - - 1.0 23.8 - - - - - - - - 2.8 - - 2.6 0.4 - - 2.8 0.6 - - - - 6.4
Kinglake West (Wallaby Creek) 6.0 11.4 0.8 0.2 0.2 0.4 23.0 0.2

- - 0.2

4.0 0.2
2.4 1.0 - - 1.2 0.8 - -
-
-
Koo Wee Rup





17.4
2.2 -



















Lancefield 4.8 2.8 - - - 1.6 3.8 - - - - - - - - 1.6 - - 4.0 - - - 1.8





Laverton RAAF 1.4 3.8 - - - - 0.8 - - - -
- - 0.2 2.4 0.2 - 2.2 0.2 - - 0.4 - - - - - 0.2 -
Main Ridge - - - 15.0 10.7 - - - - - - - 15.8 - - 4.8 - - - 4.4 - - - 10.2 1.8
Melbourne (Olympic Park) 2.2 3.0 - - - - 3.4 0.2 - - - - - - 0.2 2.0 - - 3.0 0.8 - - 0.2 - - - - - 1.2 0.2
Melbourne Airport 0.6 3.6 0.4 - - - 4.2 - 0.2 - - - - - - 1.6 - - 0.6 3.4 - - 1.0 - - - - - 0.6 0.2
Mitcham 5.4 1.8 1.2 - -
5.2 -

- - -

4.6 -
1.4 - - - 0.2
- -
-
-
Moorabbin Airport 4.0 1.0 1.0 - 0.2 1.8 4.2 - - - - - - - 0.8 3.8 - - 4.0 0.2 - - - - - - - - 4.8 -
Newham (Cobaw) 3.8 - - - 1.4 5.4 - - - - - - - - 1.4 - - 3.0










Oakleigh (Metropolitan Golf Club) 6.2 2.8 - - 1.2 4.6 - - - - - - - 3.0 5.2










Preston Reservoir 2.6 6.4 0.2 - -
2.2 -

- - -

3.8 -

0.6 - - 0.4
- -
-
-
Romsey 4.8 0.4 0.2
























Rosebud (Country Club) 5.0 2.2 - - 3.8 9.8 - - - - - - - - - 11.8












Scoresby Research Institute 5.2 1.0 0.4 - - 0.2 12.0 - - - - - - - 0.6 4.0 - - 3.8 - - - 0.6 0.4 - - - - 4.8 -
Springvale (Sandown) - - 3.6 - - - 4.8 - - - - - - - - 4.4 - - 4.8










Springvale Necropolis 4.9 - - - 5.0 - - - - - - - 3.2 - 7.0










Toolangi (Mount St Leonard DPI) 17.6 - - - 25.2 - - - - - - - 3.2 - 1.4 - - - - - - - - - 5.4
Toorourrong Reservoir (Toorourrong) 4.0 5.6 - 0.2 -
16.4 -

- - -

1.6 -
0.2 0.2 - -

- -
-
-
Upper Plenty 3.2 6.2 0.2 - - - 12.6 - - - - - - - - 1.2 - - 1.6 - - - 0.8 0.6 - - - - 2.8
Viewbank 3.4 3.8 - - - - 1.4 - - - - - - - 0.6 3.0 - - - - - - 0.2 - - - - - 2.8 -
Wallan 1.2 3.6 - - - - 3.6 - - - - - - - - 1.4 - - 2.0 0.2 - - 0.6 - - - - - 2.0
Wallan (Kilmore Gap) 2.2 1.8 0.2 - - 0.2 7.8 - - - - - - - - 1.0 - - 1.2 - 0.2 - 0.6 0.2 - - - - 2.2 0.2
Warburton (O'Shannassy Reservoir (Quarte 14.4 3.8
0.8 -

- 0.2
- 1.0 -

5.4 0.2
6.2 - - - 0.4
- -
-
0.4
Willowmavin (Avalon Station) 3.6 1.6 0.2 - - 1.6 6.0 0.2 - 0.2 - - 0.2 - - 1.0 - - 2.2 0.2 - - 0.2 - - - - - 0.8 -
Woodend 4.4 0.8 1.0 - - 1.6 9.0 - 0.2 - 0.2 - - - 0.2 1.4 - - 3.4 0.8 - - 1.8 - 0.2 - - - 1.2 -
Yan Yean 1.6 4.4 0.2 - -
2.6 -

- - -

1.6 -
1.0 0.8 0.2 -

- -
-
0.2
Yarra River @ Warrandyte 4.8 1.0 0.4 - - - 2.8 - - - - - - - 0.2 2.6 - - - - - - - - - - - - 1.4 -
Most values are the precipitation in the 24 hours to 9 am on the day indicated. Days marked with → are part of a longer accumulation, which is shown on the final day.
Values over 100 mm have been rounded to the nearest whole millimetre.
Days marked with - have a rainfall report of zero; days left blank have no rainfall report (which often indicates no rain fell).
Rainfalls coloured
according to the amount
0 1.0 5.0 10.0 15.0 25.0 50.0 100 150 200 300 400 600 millimetres

Notes

The Monthly climate summary, generally published on the first working day of each month, lists the main features of the weather in Greater Melbourne using the most timely and accurate information available on the date of publication; it will generally not be updated. More extensive discussion of significant weather events, along with later information and data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review.

This summary includes data from observing sites in or near the Greater Melbourne “Greater Capital City Statistical Area” (GCCSA). The Australian Bureau of Statistics designed the GCCSAs to “include the population within the urban area of the city, as well as people who regularly socialise, shop or work within the city, and live in small towns and rural areas surrounding the city. It is important to note that GCCSAs do not define the built up edge of the city. They provide a stable definition for these cities and are designed for the output of a range of social and economic survey data.

This statement has been prepared based on information available at 10 am on Monday 1 October 2018. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

In some situations, some or all of the rainfall is in the form of hail or snow. In these cases the totals given are for the water equivalent: the depth of liquid water that results from melting any frozen precipitation. There can be significant 'undercatch' of snow in strong winds, meaning the true precipitation can be higher than that reported.

Averages for individual sites 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.
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.

Where temperature area averages are mentioned, they are derived from the ACORN-SAT dataset.

Further information

Media
(03) 9669 4057
Enquiries