Greater Perth in October 2017: Mild days and cool nights

Mean maximum temperatures were generally close to average or below average, while mean minimum temperatures were above average for most sites in Greater Perth. Rainfall was mostly below average to near average on the coastal plain.

Below average to near average rainfall for the coastal plain sites

  • Monthly rainfall ranged from 20 mm to 40 mm for most coastal plain sites, increasing to 70 mm to 90 mm in the hills
  • There were generally 11 or 12 rain days, with a 6-day dry spell at the start of month, though daily rainfall was mostly less than 10 mm

Near average to below average mean maximum temperatures; above average mean minimum temperatures

  • Perth experienced a wintry day on the 7th with daily maxima mostly in the mid-teens; 16.1 °C at Perth Airport was its coldest October day for 25 years since 14.7 °C on 6 October 1992, while Swanbourne set its new record
  • A number of warm days with daily maxima in the high-20s to low-30s occurred on the 13th and 14th, and between the 20th and 22nd, with the 13th being the warmest day for most sites
  • Most sites recorded their highest minimum for the month on the 22nd with minima in the high teens

Perth Metro

  • October rainfall was 42.0 mm, which was the wettest October for six years, since 2011
  • October rain days were 14, the highest number in October for 12 years, since 2005
  • Mean maximum temperature was 23.1 °C, which was 0.3 °C below the long-term average
  • Highest temperature was 31.0 °C on the 13th; the first time in 10 years when temperatures in October have remained below 32 °C
  • Lowest daily maximum temperature was 16.2 °C on the 7th; the coldest October day for 10 years, since 27 October 2007 with a daily maximum of 16.0 °C
  • Mean minimum temperature was 11.9 °C, which is 0.4 °C above the long-term average
  • Highest daily minimum temperature was 18.1 °C on the 22nd, which was the warmest October morning for 5 years, since 13 October 2012 with a daily minimum of 18.4 °C
  • Lowest daily minimum temperature was 5.8 °C on the 9th, which was the equal coldest October morning for 3 years, since 7 October 2014 with a daily minimum of 5.8 °C

Further information

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Extremes in October 2017
Hottest day 32.0 °C at Gosnells City on the 13th
32.0 °C at Medina Research Centre on the 13th
Warmest days on average 23.9 °C at Millendon (Swan Valley)
Coolest days on average 20.3 °C at Bickley
Coldest day 12.3 °C at Bickley on the 7th
Coldest night 3.5 °C at Pearce RAAF on the 9th
Coolest nights on average 9.6 °C at Bickley
Warmest nights on average 14.0 °C at Rottnest Island
13.4 °C at Mandurah
Warmest night 19.6 °C at Mandurah on the 22nd
Warmest on average overall 17.5 °C at Perth Metro
Coolest on average overall 14.9 °C at Bickley
Wettest overall 92.4 mm at Huntly
Driest overall 14.8 mm at Rottnest Island
Wettest day 25.2 mm at Huntly on the 17th
Strongest wind gust 100 km/h at Ocean Reef on the 16th

Record lowest October daily maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
October
Swanbourne 15.8 on the 7th 15.9 on the 6th in 1994 25 22.3



Summary statistics for October 2017
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
October
2017
Diff
from
average
Highest for
October
2017
Mean for
October
2017
Diff
from
average
Lowest for
October
2017
Total for
October
2017
Average
for
October
Rank of
October
2017
Fraction of
October
average
Bickley 20.3 -0.9 28.5 13th 9.6 -0.1 5.0 4th 83.8 65.8 high 127%
Jandakot Aero 22.8 -0.1 30.8 13th 10.6 +0.9 4.3 6th 39.8 46.2 average 86%
Mandurah 21.5 -0.4 31.1 13th 13.4 0.0 8.8 5th 25.0 30.1 average 83%
Medina Research Centre 23.2 +0.4 32.0 13th 11.2 +0.8 4.4 9th 23.5 39.0 low 60%
Millendon (Swan Valley) 23.9   31.3 13th 10.3   3.8 9th 30.4
Pearce RAAF 23.5 0.0 31.3 31st 10.6 +0.5 3.5 9th 26.2 35.9 average 73%
Perth Airport 23.2 +0.5 31.4 13th 10.8 +0.5 3.9 9th 25.6 43.3 low 59%
Perth Metro 23.1 -0.3 31.0 13th 11.9 +0.4 5.8 9th 42.0 51.5 average 85%
Rottnest Island 20.7 +0.2 28.4 21st 14.0 0.0 9.8 4th 14.8 28.7 low 52%
Swanbourne 21.9 -0.4 31.2 13th 12.9 +0.5 7.7 4th 26.4 42.7 low 62%
Note: Observations for “Perth Metro” are taken from the current site at Mount Lawley (Bureau number 009225).
Comparisons are made against combined data from the current site (which opened in early 1993) and the previous site at Perth Regional Office (009034), which ran from 1876 to early 1992.

Daily maximum temperatures for October 2017
12345678910111213141516171819202122232425262728293031
Bickley22.121.818.016.718.919.512.316.320.315.517.622.528.524.124.315.916.716.321.827.226.326.119.820.319.917.115.617.118.224.627.9
Garden Island HSF22.818.319.618.619.519.819.517.423.930.228.526.620.520.422.020.919.220.518.720.219.7
Gosnells City25.724.220.022.023.016.922.332.029.025.821.220.319.526.030.630.029.023.322.922.820.120.521.527.1
Jandakot Aero24.722.921.419.821.021.316.518.921.019.119.123.330.826.823.920.519.919.124.429.729.929.023.422.123.022.319.020.920.125.727.9
Karnet23.520.616.715.519.518.517.519.216.316.428.525.524.516.717.116.122.027.026.419.120.018.518.025.0
Mandurah23.520.619.918.822.619.115.717.918.719.618.121.431.124.121.318.818.518.325.330.929.125.421.820.721.119.219.219.419.221.425.0
Medina Research Centre26.421.921.320.222.223.016.019.520.920.218.922.832.029.024.021.721.418.825.031.030.030.322.222.624.422.820.022.021.324.3
Millendon (Swan Valley)24.424.420.919.321.723.316.320.023.520.320.125.431.329.027.020.920.119.824.529.529.829.524.024.023.223.121.022.321.628.430.9
Pearce RAAF24.924.121.119.021.022.217.219.622.619.919.324.730.527.926.320.520.219.924.529.629.828.824.023.623.221.220.122.221.928.431.3
Perth Airport24.924.021.720.021.922.016.119.621.919.019.524.531.428.225.419.920.119.424.729.929.528.423.622.622.720.919.320.520.627.529.3
Perth Metro25.122.921.519.722.121.916.220.021.820.419.223.831.027.224.620.220.619.524.729.930.328.423.822.523.021.219.521.220.227.128.1
Rottnest Island23.519.718.617.818.119.916.417.418.019.118.619.725.824.920.619.019.318.720.728.328.426.321.020.422.121.019.120.018.821.220.5
Swanbourne24.720.221.419.721.420.915.818.119.019.518.822.031.224.821.619.719.618.724.530.630.025.222.721.123.120.919.521.019.621.922.5
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 October 2017
12345678910111213141516171819202122232425262728293031
Bickley7.410.37.75.05.36.86.26.56.58.66.67.010.813.713.613.311.08.16.49.512.715.214.412.611.512.67.910.78.88.212.6
Garden Island HSF12.213.512.49.89.07.514.110.014.917.017.017.215.716.716.514.714.815.111.715.5
Gosnells City11.59.88.29.510.09.48.65.910.017.515.414.010.09.614.515.019.015.514.511.39.214.113.711.111.1
Jandakot Aero8.37.78.86.38.04.38.57.54.57.910.15.211.515.116.315.313.412.45.112.316.216.914.413.29.514.311.414.112.46.910.6
Karnet8.58.05.55.65.54.56.55.46.514.53.86.65.010.511.49.012.812.0
Mandurah11.413.612.49.48.810.99.611.09.313.512.210.514.016.816.915.414.613.19.214.116.219.617.015.016.616.213.515.314.211.114.0
Medina Research Centre6.68.47.07.54.59.012.04.48.710.17.012.614.016.015.413.713.05.412.717.017.013.313.311.015.713.314.013.08.510.7
Millendon (Swan Valley)9.07.06.97.39.35.39.67.03.88.19.86.212.713.214.915.312.58.96.512.016.518.214.514.88.913.18.311.911.97.47.8
Pearce RAAF9.98.97.27.89.25.89.06.63.58.99.66.012.314.015.314.813.410.75.913.417.918.415.114.59.212.89.211.011.17.58.4
Perth Airport9.07.77.87.39.55.69.37.23.98.410.06.013.915.116.415.313.912.06.812.115.918.514.314.39.613.38.414.012.67.98.7
Perth Metro9.48.410.37.89.56.59.78.45.810.111.79.114.415.016.015.413.813.38.312.916.918.116.714.311.014.813.114.513.48.711.6
Rottnest Island12.815.413.19.810.011.911.512.112.613.113.612.514.818.315.614.813.212.711.415.217.619.116.815.115.515.213.614.414.612.515.6
Swanbourne11.012.010.97.79.48.99.811.28.312.711.99.014.317.416.015.013.813.98.714.918.218.117.014.215.915.813.214.414.29.912.7
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 October 2017
12345678910111213141516171819202122232425262728293031
Anketell - - - - - - 3.8 2.2 - - 4.4 - - 1.0 - 7.6 6.4 4.4 - - - 0.2 - - - 1.8 3.4 1.0 1.0 - -
Bickley - - - - - - 2.4 0.6 - - 1.4 0.2 - 17.6 - 9.6 15.6 9.6 - - - 3.0 - - - 4.0 10.2 5.6 3.8 - 0.2
Bungendore - - 0.2 - - - 2.6 1.0 0.2 - 2.0 - - - - 8.8 13.6 7.2 - - - 3.0 - - 0.2 2.6 7.8 1.4 3.2 - -
Chidlow - - - - - - 1.0 - - 0.2 2.0 - - 3.0 1.6 12.2 5.8 - - - 24.4 - - 1.6 4.0 1.6 1.8
Garden Island HSF - - - - - -











- - - - - - - - 2.6 - 0.2 - -
Gosnells City - 2.4 0.9 - 7.8 7.0 2.2 - - - - - - 1.8 5.4 1.5 1.1 - -
Halls Head - - - - - - 2.8 2.6 0.2 - - - - - - 2.2 6.0 8.5 - - - - - - 1.0 1.2 1.6



Herne Hill - - - - - - 1.6 0.4 - - 1.6 - - - - - 8.6 13.0 - - - 1.8 - - - 1.2 1.2 1.0 - - -
Huntly - - - - - - 2.8 1.8 - 0.2 5.2 - - - - 11.0 25.2 12.0 0.8 - - 2.8 5.2 - 1.6 5.6 12.8 2.0 3.4

Jandakot Aero - - - - - - 2.6 2.8 - - 1.8 - - 2.2 - 7.8 9.6 5.2 - - - - - - 0.6 0.6 5.2 1.0 0.4 - -
Jarrahdale 0.2 0.4 0.2 - - - 2.8 0.8 0.4 0.2 2.2 - 0.2 - - 9.6 23.2 13.2 0.2 - - 3.6 0.2 - 0.2 3.4 9.8 2.8 5.4 - 0.4
Karnet 0.2 - - - -

0.6 - - 3.6 -
- -
14.8 10.6 - - -
-
1.6 6.4 10.4 -
Karragullen North - - 2.4 3.2 - - 2.2 - 9.6 19.4 7.4 - - - 1.8 - - - - - - - - - - 2.0 9.6 5.4 4.2

Maida Vale - - - - - - 2.0 1.2 - 0.4 1.6 - - 2.2 - 4.0 8.2 5.8 - - - 1.4 - - 0.2 2.4 4.0 2.0 - - -
Mandurah - - - - - - 2.8 2.6 0.2 - - - - - - 2.2 2.2 11.6 0.2 - - - - - 0.8 0.8 1.4 - 0.2 - -
Medina Research Centre - - - - - - 5.6 1.0 - - 2.4 - - 1.2 - 3.0 3.6 3.2 - - - - - - 0.2 0.3 1.8 0.9 0.3 - -
Midland - - - - - - 2.0 - 3.8 - - 6.8 8.8 7.8 - - 0.6 - - 1.2 0.8 - - - -
Millendon (Swan Valley) - - - - - - 1.6 0.2 - - 2.6 - - 0.6 - 5.6 8.0 7.4 0.2 - - 1.0 - - -
1.4 0.4 1.4 - -
Mount Helena





2.0 0.6

3.2

1.8
3.4 14.2 8.2


16.2


1.0 6.8 3.0 3.6

Mount Solus - 0.2 - - - - 1.6 0.4 - - 2.0 - - 0.6 0.2 4.8 23.8 7.2 0.2 - - 2.6 0.2 - 1.6 4.8 11.0 2.4 5.0 - -
Muchea - - - - - - 1.4 0.6 - 0.8 2.8 0.2 - 1.2 - 3.0 5.2 4.6 - - - 0.8 - - - 0.2 2.6 0.4 0.8 - -
Mundaring - - - - - - 2.2 1.2 - 0.4 2.4 - - 2.4 - 7.2 18.6 13.0 0.2 - - 2.6 - - - 3.2 5.4 6.6

Noble Falls





1.0

0.4 2.2

1.2
4.0 11.0 6.0


4.6



7.0



Pearce RAAF - - - - - - 1.0 0.2 - - 5.6 - - 0.4 - 3.4 5.6 3.6 - - - 0.8 - - - 0.4 3.0 0.4 1.8 - -
Perth Airport - - - - - - 1.4 0.2 - - 2.2 - - - - 3.0 7.6 5.0 - - - 1.0 - - - 1.0 2.2 1.2 0.8 - -
Perth Metro - - - - - - 1.6 0.6 - 0.2 4.8 - - 2.4 - 6.6 10.6 6.6 0.2 - - 0.6 - - - 1.2 4.2 1.4 1.0 - -
Pickering Brook





3.2 0.4

11.8

3.6
8.4 17.0 11.6



2.8

4.4 8.0 4.6 3.8

Pinjarra Refinery - - - - - - 2.8 0.8 - 0.6 2.2 - - 0.4 - 5.0 6.6 6.4 - - - 1.2 - - 0.8 3.0 6.4 0.4 1.2 - -
Pinjarra South - - - - - - 4.8 1.4 - - 3.0 - - - - 4.4 5.0 6.6 - - - - - - - 1.0 6.4 0.4 - - -
Roleystone - - - - - - 7.4 0.6 - 1.0 2.6 - - 0.8 - 8.2 18.8 9.8 - - - 2.2 - - 0.6 3.0 7.2 3.3 3.0

Rottnest Island - - - - - - 1.0 - - 0.2 0.2 - - - - 4.4 2.8 2.0 0.4 - - 0.2 0.2 - 0.2 1.0 2.2 - - - -
Serpentine - - - - - - 1.4 0.8 - - 0.6 - - - - 6.2 11.0 9.2 - - - - - - 0.6 1.0 5.4 0.8 2.0 - -
Swanbourne - - - - - - 2.0 1.4 - - 1.6 - - 0.4 - 7.6 4.8 4.4 - - - 0.4 - - - 2.2 1.0 0.4 0.2 - -
Tamala Park (Mindarie) - -




























Wanneroo - - - - - - - - - - 2.6 - - 9.0 6.0 5.8 - - 0.4 - - 0.2 0.8 3.2
Werribee - - - - - - 0.2 0.4 - - 2.4 - - 0.4 - 2.6 8.4 3.6 - - - 3.6 - - - 1.8 4.4 0.6 1.0 0.2 -
Whiteman Park - - - - - - 2.4 0.8 - - 2.4 - - 1.0 - 6.4 9.2 5.2












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 Perth 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.

In September 2017 this summary was broadened to include data from observing sites in or near the Greater Perth “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 9 am on Wednesday 1 November 2017. 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