Greater Perth in November 2020: a record wet November, mild temperatures

Most locations across Greater Perth, including the Perth Metro site had their wettest November on record. Mean maximum temperatures were all cooler than average and it was the third-coolest November on record and coolest for over a decade at the Perth Metro site. Mean minimum temperatures were slightly cooler than average.

Above average rainfall for all sites

  • Monthly rainfall in November 2020 was more than double of November average across Greater Perth, and close to 4 times the average at Bickley; monthly totals ranged from 50–100 mm for most sites, up to 120–170 mm in the Perth hills.
  • During the first half, and on the last day of November, a series of cold fronts and associated low pressure systems produced 4 periods of rain across Greater Perth; rain days were between the 1st and 3rd, between the 9th and 11th, between the 13th and 15th, and the 30th.
  • Most sites, including sites with over 50 years of record, such as Perth Airport, had their wettest November on record.
  • Perth Metro recorded a monthly total of 92.0 mm, its wettest November in 27 years of rainfall record; it was also the wettest November on record for any central Perth sites with rainfall observations dating back to 1867.
  • Widespread moderate rainfall of 20– 60 mm in 24 hours to 9am on the 10th was recorded across Perth; several sites in the Perth hills had their wettest November day on record.

Below average daytime temperatures

  • Mean maximum temperatures were generally 1–2 °C below average, though the mean maximum temperature at Bickley in the Perth hills was 3 °C cooler than its November average.
  • Perth Metro recorded a mean maximum temperature of 24.7 °C, which was its third-coolest November days on record and coolest since 2008 (23.6 °C); Perth Airport's mean maximum temperature of 25.0 °C was also its coolest November since 2008 (23.9 °C).
  • Daytime temperatures were generally in the mid-10s to mid-20s, and coastal plain sites reported 2 consecutive days of 32 °C or higher in late November on the 23rd and 24th; the lowest temperature was 15.1 °C at Bickley on the 1st and the highest was 36.4 °C at Pearce RAAF on the 23rd and at Millendon (Swan Valley) on the 24th.
  • Perth Metro recorded a maximum temperature of 18.4 °C on the 1st, its coolest November day for 18 years since 1 November 2002 (17.7 °C).
  • Mean minimum temperatures were generally less than 1 °C cooler than average.
  • Nights were generally cool or mild with daily minimum temperatures in the 10s, and cold nights with daily minima below 10 °C were observed at coastal plain sites between the 10th and 12th.

Perth Metro

  • Total rainfall for Perth Metro was 92.0 mm, which is 380% of the long-term average of 24.2 mm
  • The mean daily maximum temperature for Perth Metro was 24.7 °C, which is 2.1 °C below the long-term average of 26.8 °C
  • The warmest day was 35.1 °C on the 23rd, and the coolest day was on the 1st when the temperature reached 18.4 °C
  • The mean daily minimum temperature for Perth Metro was 13.5 °C, which is 0.9 °C below the long-term average of 14.4 °C
  • The coldest morning was 8.0 °C on the 12th, and the warmest morning was on the 24th when the minimum temperature was 16.8 °C

Further information

Media
(03) 9669 4057

Extremes in November 2020
Hottest day 36.4 °C at Pearce RAAF on the 23rd
36.4 °C at Millendon (Swan Valley) on the 24th
Warmest days on average 25.8 °C at Pearce RAAF
Coolest days on average 22.0 °C at Rottnest Island
Coldest day 15.1 °C at Bickley on the 1st
Coldest night 6.0 °C at Jandakot Aero on the 12th
Coolest nights on average 11.0 °C at Karnet
Warmest nights on average 15.5 °C at Rottnest Island
Warmest night 20.6 °C at Garden Island HSF on the 24th
Warmest on average overall 19.4 °C at Gosnells City
Coolest on average overall 16.6 °C at Bickley
Wettest overall 169.4 mm at Bickley
Driest overall 54.4 mm at Rottnest Island
Wettest day 63.4 mm at Mundaring on the 10th
Strongest wind gust 83 km/h at Ocean Reef on the 10th

Record highest November daily rainfall
New record
(mm)
Old
record
Years of
record
Mundaring 63.4 on the 10th 57.2 on the 15th in 1948 108
Gidgegannup 53.4 on the 10th 48.0 on the 8th in 1984 60
Roleystone 53.6 on the 10th 42.8 on the 19th in 2009 53
Karragullen North 52.4 on the 10th 37.0 on the 19th in 2009 49



Record highest November total rainfall
New record
(mm)
Old
record
Years of
record
Average for
November
Mundaring 142.2 118.9 in 1946 117 33.4
Serpentine 91.8 81.3 in 1946 98 24.7
Perth Airport 89.0 84.8 in 2012 77 26.3
Gidgegannup 137.8 85.0 in 1983 59 27.4
Gosnells City 100.2 93.4 in 1992 58 29.7
Roleystone 132.2 90.0 in 1984 53 36.6
Bickley 169.4 128.6 in 2012 51 43.1
Karragullen North 142.8 115.6 in 2012 49 39.6
Jandakot Aero 81.4 78.6 in 2008 47 28.3
Huntly 133.3 122.2 in 2012 29 49.8
Rottnest Island 54.4 52.0 in 1999 29 19.5
Perth Metro 92.0 58.2 in 2012 28 24.2
Mandurah 63.4 57.2 in 2012 20 24.0
Pinjarra South 91.0 68.2 in 2011 20 27.7

Highest November total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Average for
November
Chidlow 104.9 117.6 in 1946* 26.3
Wanneroo 72.8 76.4 in 1984* 21.6
Jarrahdale 116.2 129.4 in 1984* 35.4

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




Summary statistics for November 2020
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
November
2020
Diff
from
average
Highest for
November
2020
Mean for
November
2020
Diff
from
average
Lowest for
November
2020
Total for
November
2020
Average
for
November
Rank of
November
2020
Fraction of
November
average
Bickley 22.1 -3.0 33.5 24th 11.2 -0.7 7.5 10th 169.4 43.1 highest 393%
Garden Island HSF 22.4 -1.4 30.1 6th 15.4 -0.3 10.4 12th 57.0 21.9 v high 260%
Gosnells City 25.4 -2.3 36.0 23rd 13.7 -0.8 8.1 12th 100.2 29.7 highest 337%
Jandakot Aero 24.3 -2.2 34.7 23rd 12.5 -0.2 6.0 12th 81.4 28.3 highest 288%
Karnet     33.2 23rd 11.0 -0.4 6.3 12th        
Mandurah 23.1 -1.8 32.5 23rd 15.2 -0.4 11.4 10th 63.4 24.0 highest 264%
Millendon (Swan Valley) 25.6   36.4 24th 12.3   6.6 12th 102.2
Pearce RAAF 25.8 -1.6 36.4 23rd 12.8 +0.2 7.2 12th
Perth Airport 25.0 -1.1 36.1 23rd 12.5 -0.3 7.4 12th 89.0 26.3 highest 338%
Perth Metro 24.7 -2.1 35.1 23rd 13.5 -0.9 8.0 12th 92.0 24.2 highest 380%
Rottnest Island 22.0 -1.1 27.7 6th 15.5 -0.5 11.3 10th 54.4 19.5 highest 279%
Swanbourne 23.2 -2.2 32.6 23rd 14.4 -0.4 10.3 12th

Daily maximum temperatures for November 2020
123456789101112131415161718192021222324252627282930
Bickley15.118.319.421.827.425.626.822.818.015.816.819.519.017.717.522.620.622.324.723.624.027.733.333.526.522.720.822.821.415.5
Garden Island HSF18.820.720.223.226.430.125.623.218.817.819.121.721.521.420.622.422.623.722.423.821.026.227.724.324.423.022.219.720.117.9
Gosnells City18.723.122.526.131.129.530.125.518.519.020.622.723.522.021.325.323.425.127.226.429.229.536.034.529.525.024.024.823.9
Jandakot Aero18.122.322.325.831.029.228.424.918.119.620.422.223.021.721.023.122.124.025.026.025.427.934.732.228.223.923.123.222.320.1
Karnet16.520.322.527.425.626.622.822.517.017.019.220.219.417.522.920.020.423.823.123.027.633.230.926.222.920.7
Mandurah18.019.420.825.429.330.725.923.418.419.120.220.821.421.520.522.121.422.923.023.423.426.432.528.626.124.722.621.820.918.8
Millendon (Swan Valley)17.621.223.424.730.828.830.127.022.219.320.723.122.422.621.425.925.326.527.627.326.529.736.236.429.726.124.425.525.219.6
Pearce RAAF17.921.724.326.031.228.830.226.823.120.820.323.822.622.121.626.525.526.627.026.827.331.036.436.130.625.324.425.224.820.4
Perth Airport18.521.323.026.031.129.229.225.421.219.121.322.322.121.021.124.723.425.026.326.026.029.336.134.829.724.223.424.323.620.2
Perth Metro18.422.222.825.930.529.229.625.518.619.020.822.722.921.622.124.323.525.225.726.325.228.235.133.728.924.123.523.523.619.4
Rottnest Island18.120.920.622.124.627.725.523.018.618.819.021.721.520.519.921.721.422.821.923.721.824.326.424.923.522.922.020.420.818.7
Swanbourne18.221.421.225.128.829.726.823.818.018.619.021.621.321.320.622.522.123.923.224.222.427.732.627.625.623.122.521.721.918.5
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 November 2020
123456789101112131415161718192021222324252627282930
Bickley12.011.111.79.89.012.312.412.17.57.68.213.211.98.610.210.413.510.912.611.111.414.018.612.912.69.68.111.210.3
Garden Island HSF15.314.515.413.813.916.517.218.615.712.612.710.416.716.313.615.916.918.615.817.415.615.413.720.616.716.415.213.212.313.7
Gosnells City15.213.413.513.912.216.517.014.914.010.29.68.116.814.110.611.117.014.514.814.012.515.019.214.515.313.99.913.014.0
Jandakot Aero14.912.712.412.912.815.815.913.411.710.39.86.015.512.511.710.410.113.110.912.411.714.113.016.715.013.312.47.211.213.7
Karnet13.411.110.410.012.413.712.110.47.76.76.312.711.07.98.29.212.99.811.910.311.515.117.014.612.510.28.5
Mandurah15.415.015.313.513.416.316.617.716.711.412.211.415.816.313.014.214.918.215.516.914.615.218.020.515.616.314.512.715.013.9
Millendon (Swan Valley)15.113.712.312.912.815.716.112.711.69.38.36.614.014.59.89.310.912.910.912.911.212.913.717.813.112.113.19.09.713.2
Pearce RAAF15.213.713.212.613.416.016.912.311.69.810.57.214.314.010.610.911.412.611.212.111.814.214.719.313.412.414.010.110.113.4
Perth Airport14.913.111.412.813.015.816.013.912.510.57.67.414.413.911.410.111.113.310.613.212.414.413.116.015.011.911.98.310.613.3
Perth Metro15.013.613.013.713.116.016.214.813.110.69.28.016.314.412.610.711.714.514.314.414.114.914.616.815.513.814.010.811.613.6
Rottnest Island14.514.314.814.214.216.517.517.316.211.313.013.716.115.811.715.315.717.516.317.616.315.918.319.516.916.716.014.415.213.5
Swanbourne14.913.214.413.713.616.316.616.116.210.810.710.316.114.712.912.314.017.815.115.714.515.316.119.115.714.414.511.612.313.6
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 November 2020
123456789101112131415161718192021222324252627282930
Anketell 19.6 9.3 2.1 0.1 - - - - 7.9 34.8 1.2 - 8.2 2.3 7.9 0.2 - - - - - - - - - - - - - 6.6
Bickley 20.6 19.0 1.8 - - - -
0.4 59.2 0.8 - 14.2 8.8 32.8 - - 0.4 0.2 - - -
- - - - -
11.2
Bungendore 17.6 12.2 0.4 0.2 - - - - 6.0 37.0 1.0 - 11.4 2.0 19.0 - - 0.2 0.6 - - - - - - - - - - 11.8
Chidlow 21.7 12.0 - - - 0.1 36.6 0.4 - 5.0 7.0 7.9 - - - - - - - - - - - - 14.2
Garden Island HSF 14.8 6.2 0.8 - - - - - 4.2 17.0 - - 4.6 1.6 5.0 - - - 0.4 - - - - - - - - - - 2.4
Gidgegannup 13.2 13.0 4.6 - - - - - 0.2 53.4 0.8 - 9.0 7.2 23.6 - - - - 0.2 - - - - - - - - - 12.6
Gosnells City 17.2 11.0 3.0 - - - - - 12.0 19.4 0.8 - 11.6 5.4 13.6 - - - - - - - - - - - - - - 6.2
Huntly 17.0 6.2 1.0 - - - - - - 62.0 1.0 - 12.0 1.1 19.2 0.4 - - - - 1.8 - - - - - - - - 11.6
Jandakot Aero 15.4 10.6 1.4 - - - - - 3.2 25.2 - - 9.6 0.8 10.4 - - - - - - - - - - - - - - 4.8
Jarrahdale 16.0 8.8 0.6 0.2 - - - - 7.6 38.4 1.0 - 8.2 1.0 23.2 0.2 - 0.4 0.2 - - 0.2 - - - - - - - 10.2
Karnet 15.8 7.3 - - - - - - 5.6 45.9 - - 8.2 1.4 28.6 0.2 - 0.6 1.2 - - - - - - - - -

Karragullen North 19.0 14.4 1.0 - - - - - 0.6 52.4 - - 9.6 5.6 24.2 - - 0.4 - - - - - - - - - - - 15.6
Maida Vale 19.4 12.6 2.4 - - - - - 0.2 27.0 2.2 - 10.2 5.8 12.4 - - 0.2 - - - - - - - - - - - 4.2
Mandurah 17.0 4.6 6.8 0.2 - - - - 3.4 12.0 - - 6.8 - 8.4 - - - 0.2 - - - - - - - - 0.2 - 3.8
Millendon (Swan Valley) 14.0 11.0 9.8 - - - - - - 38.6 0.2 - 5.4 5.8 12.2 - - - - - - - - - - - - - - 5.2
Mount Solus 16.0 11.6 1.4 - - - - - 2.8 40.0 0.8 - 6.2 0.8 20.8 - - 0.4 1.2 - - - - - - - - - - 8.0
Muchea 11.4 8.6 1.4 - - - - - - 37.2 0.6 - 9.6 8.2 14.8 - - - - - - - - - - - - - - 2.2
Mundaring 15.6 13.0 2.2 - - - - - - 63.4 2.8 - 6.8 7.4 21.0 - - - - - - - - - - - - - - 10.0
Perth Airport 17.4 11.2 2.2 - - - - - - 21.0 0.6 - 10.4 4.4 14.4 - - - - - - - - - - - - - - 7.4
Perth Metro 20.6 11.6 3.8 0.2 - - - - 2.0 19.0 - - 8.8 4.0 13.6 - - - - - - - - - - - - - - 8.4
Pinjarra South 23.6 3.2 7.6 - - - - - 6.2 22.0 0.2 - 4.0 1.0 9.8 - - - 0.2 - - - - - - - - - - 13.2
Roleystone 20.0 15.8 3.2 - - - - - 0.6 53.6 0.8 - 9.8 6.2 13.8 - - 0.6 - - - - - - - - - - - 7.8
Rottnest Island 16.4 3.2 4.6 - - - - - 4.0 10.4 0.4 - 2.8 0.4 8.0 - - - - - - - - - - - - - - 4.2
Serpentine 16.8 6.6 0.2 - - - - - 4.8 32.2 0.8 - 7.4 1.8 14.2 0.2 - - 0.8 - - - - - - - - - - 6.0
Swanbourne


0.4
- - - 5.2 16.2 - - 0.4




- - - - - - - - - 0.2 - 6.2
Tamala Park (Mindarie) 14.0 8.6 3.2 - - - - - 0.1 17.7 0.3 - 6.4 3.6 5.4 - - - - - - - - - - - - - 0.1 5.6
Wanneroo 22.0 1.2 - - - - - 18.2 0.8 - 7.4 9.6 - - - - - - - - - - - 13.6
Werribee 8.0 9.8 0.6 - - - - - - 28.2 - - 5.0 6.8 13.0 - - - - - - - - - - - - - - 4.2
Whiteman Park 16.0




























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.

This summary includes 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 Tuesday 1 December 2020. 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

Climate