Tuesday, 1 December 2020 - Monthly Climate Summary for Greater Perth - Product code IDCKGC11L0

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

Extremes Maps Records Summaries Daily observations Important notes the top

Extremes Maps Records Summaries Daily observations Important notes the top

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

Extremes Maps Records Summaries Daily observations Important notes the top

Extremes Maps Records Summaries Daily observations Important notes the top

Extremes Maps Records Summaries Daily observations Important notes the top