Greater Sydney in summer 2021-22: A wet summer with cool days and warm nights

Very humid conditions were associated with above average rainfall across all three summer months. Maximum temperatures were generally cooler than average while minimum temperatures were warmer than average, resulting in the mean summer temperature being close to average.

Wetter than average summer ended with a very wet February

  • Increased availability of moisture throughout summer resulted in a wetter than average summer, with much of Greater Sydney recording rainfall more than 50% to 100% above their long-term summer average.
  • Observatory Hill recorded its wettest summer since 1991–1992.
  • December rainfall was 10–40% above average across much of Greater Sydney.
  • The passage of a deep surface trough resulted in rainy weather from the 8th to the 10th of December, with widespread falls of greater than 50 mm recorded over the three-day period.
  • In January, there was a greater number of rainy days than usual, with above-average rainfall for most of Greater Sydney, especially towards the west where totals were more than 50% above their January average.
  • Stormy weather was responsible for heavy rainfall during January with storms producing between 20–50 mm in many locations over Sydney on the 6th, 8th, 13th and 14th.
  • For February, rainfall was well above average, with some parts of Greater Sydney receiving at least 2–3 times their monthly average.
  • Very moist conditions during February led to rainfall being more than 50% above the monthly average in many locations, while the number of rainy days was around twice the average for the month.
  • Baulkham Hills (Eucalyptus Ct), Concord (Brays Rd) and Wyong (Mount Elliot) had their highest total summer rainfall on record.
  • Numerous sites had their highest total summer rainfall in at least 20 years.

Cool days and warm nights

  • Maximum temperatures were around 1 to 2 °C below their seasonal average for much of Greater Sydney, except along the coast where temperatures were average to above average.
  • Minimum temperatures were around seasonal average to slightly above seasonal average for most locations.

Sydney (Observatory Hill)

  • Total rainfall for Sydney (Observatory Hill) was 655.0 mm, which is 220% of the long-term average at the former Observatory Hill site, or 222% of the average over recent decades.
  • The mean daily maximum temperature for Sydney (Observatory Hill) was 26.9 °C, which is 1.2 °C above the long-term average at the former Observatory Hill site, or 0.4 °C above the average over recent decades.
  • The warmest day was 34.6 °C on 19 December, and the coolest day was on 5 December when the temperature reached 19.7 °C.
  • The mean daily minimum temperature for Sydney (Observatory Hill) was 19.2 °C, which is 0.8 °C above the long-term average at the former Observatory Hill site, or 0.2 °C below the average over recent decades.
  • The coldest morning was 13.9 °C on 10 December, and the warmest morning was on 11 January when the minimum temperature was 22.7 °C.

Significant weather

  • A strong cold front crossed Greater Sydney on 19th December, producing damaging winds and storms.
  • Humid conditions resulted in fog blanketing Sydney during the morning of the 14th of January.
  • Repeated generation of slow-moving thunderstorms brought significant rainfall to the Sydney metropolitan area on the 22nd of February with some locations such as Marrickville receiving intense rainfall in excess of 100 mm in a 2–3-hour period.
  • Numerous locations received more than their February average and flash flooding was experienced over parts of metropolitan Sydney.
  • Towards the end of February, there was a succession of wet and very humid days due to a persistent and deep moist easterly airstream produced by a slow-moving high-pressure system in the Tasman Sea.
  • A Special Climate Statement is being prepared for the ongoing extreme rainfall and flooding event in New South Wales.

Further information

Media
(03) 9669 4057

Extremes in summer 2021-22
Hottest day 38.9 °C at Holsworthy Defence AWS on 18 Dec 2021
Warmest days on average 28.3 °C at Penrith Lakes AWS
Coolest days on average 21.5 °C at Katoomba (Farnells Rd)
Coldest day 10.1 °C at Mount Boyce AWS on 10 Dec 2021
Coldest night 5.6 °C at Mount Boyce AWS on 10 Dec 2021
Coolest nights on average 12.6 °C at Mount Boyce AWS
Warmest nights on average 20.0 °C at Sydney Harbour (Wedding Cake West)
Warmest night 23.2 °C at Sydney Harbour (Wedding Cake West) on 11 Jan 2022
Warmest on average overall 23.3 °C at Norah Head AWS
Coolest on average overall 17.2 °C at Katoomba (Farnells Rd)
17.2 °C at Mount Boyce AWS
Wettest overall 765.0 mm at Wyong (Mount Elliot)
Wettest day 170.0 mm at Marrickville Golf Club on 23 Feb 2022
Strongest wind gust 100 km/h at Mount Boyce AWS on 19 Dec 2021

Record highest summer total rainfall
New record
(mm)
Old
record
Years of
record
Average for
summer
Baulkham Hills Eucalyptus Ct 500.0 452.5 in 2019 22 292.3
Concord (Brays Rd) 519.4 476.2 in 2019 21 313.7
Wyong (Mount Elliot) 765.0 698.0 in 2012 21 375.9

Highest summer total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Average for
summer
Marrickville Golf Club 576.0 831.4 in 1955* 263.6
Randwick (Randwick St) 703.3 833.9 in 1989 292.7
Bankstown Airport AWS 509.8 614.4 in 1989* 272.8
Belrose (Evelyn Place) 613.4 847.9 in 1991 372.2
Sydney Airport AMO 559.6 561.4 in 1991 283.8
Castle Cove (Rosebridge Ave) 719.1 775.6 in 1991* 371.7
Rose Bay (Royal Sydney Golf Club) 668.4 700.6 in 1991* 303.7
Chatswood Bowling Club 621.0 911.5 in 1955* 349.5
Audley (Royal National Park) 606.0 696.0 in 1991* 297.7
Collaroy (Long Reef Golf Club) 563.4 658.9 in 1972* 324.4
Darkes Forest (Kintyre) 613.0 1283.0 in 1991* 398.2
Mona Vale Golf Club 511.2 543.4 in 1991* 307.4
Box Hill (McCall Gardens) 424.0 554.2 in 1991* 261.9
Centennial Park 654.0 805.4 in 1989* 304.6
Sydney Botanic Gardens 683.5 749.8 in 1991* 302.4

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




Summary statistics for summer 2021-22
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
summer
2021-22
Diff
from
average
Highest for
summer
2021-22
Mean for
summer
2021-22
Diff
from
average
Lowest for
summer
2021-22
Total for
summer
2021-22
Average
for
summer
Rank of
summer
2021-22
Fraction of
summer
average
Badgerys Creek AWS 27.7 -1.5 37.5 18 Dec 2021 16.7 0.0 11.2 14 Dec 2021 461.0 246.4 high 187%
Bankstown Airport AWS 27.4 -0.6 38.2 18 Dec 2021 18.3 +0.6 13.0 14 Dec 2021 509.8 272.8 v high 187%
Camden Airport AWS 27.5 -1.5 37.0 18 Dec 2021 16.8 +0.4 10.8 14 Dec 2021 426.2 246.8 high 173%
Campbelltown (Mount Annan) 27.5 -1.6 37.1 18 Dec 2021 16.4 -0.1 10.2 12 Dec 2021 370.0 246.1 high 150%
Canterbury Racecourse AWS 26.4 -0.9 36.1 1 Feb 2022 18.1 +0.2 12.8 30 Dec 2021 505.2 264.2 v high 191%
Cooranbong (Lake Macquarie AWS) 27.0 -1.2 34.9 18 Dec 2021 17.4 +0.3 11.6 15 Dec 2021 504.8 346.2 high 146%
Gosford AWS 26.1   35.2 19 Dec 2021 18.3   12.2 6 Dec 2021
Holsworthy Aerodrome AWS 27.0   38.0 18 Dec 2021 17.6   11.3 14 Dec 2021 419.0 264.2 high 159%
Holsworthy Defence AWS 26.4   38.9 18 Dec 2021 16.7   10.9 14 Dec 2021 451.4
Horsley Park Equestrian Centre AWS 27.1 -2.0 37.4 18 Dec 2021 17.3 0.0 11.9 14 Dec 2021 448.6 265.0 high 169%
Katoomba (Farnells Rd) 21.5 -1.3 30.7 21 Dec 2021 12.7 +0.2 7.0 29 Dec 2021 646.9 460.3 high 141%
Mangrove Mountain AWS 26.5 -0.4 35.7 18 Dec 2021 16.3 -0.1 10.9 10 Dec 2021 186.8 329.3 low 57%
Mount Boyce AWS 21.8 -1.5 29.3 18 Dec 2021 12.6 -0.2 5.6 10 Dec 2021 565.6 348.8 v high 162%
Norah Head AWS 26.8 +1.0 34.2 19 Dec 2021 19.7 +0.3 14.5 10 Dec 2021 395.8 275.5 high 144%
Parramatta North (Masons Drive) 27.1 -0.9 37.2 18 Dec 2021     13.0 29 Dec 2021 467.6 306.9 high 152%
Penrith Lakes AWS 28.3 -1.9 38.2 18 Dec 2021 17.9 -0.2 12.2 10 Dec 2021
Richmond RAAF 27.8 -1.8 36.1 18 Dec 2021 17.2 -0.1 10.1 12 Dec 2021 324.8 278.2 high 117%
Sydney (Observatory Hill) 26.9   34.6 19 Dec 2021 19.2   13.9 10 Dec 2021 655.0
Sydney Airport AMO 26.6 +0.2 35.9 1 Feb 2022 19.3 +0.7 14.3 10 Dec 2021 559.6 283.8 v high 197%
Sydney Harbour (Wedding Cake West) 24.3 -0.1 34.4 19 Dec 2021 20.0 +0.1 14.4 11 Dec 2021
Sydney Olympic Park AWS (Archery Centre) 27.0 -1.3 37.8 18 Dec 2021 18.5 -0.1 12.8 10 Dec 2021 467.6
Terrey Hills AWS 24.8 -1.3 34.0 19 Dec 2021 17.7 -0.1 12.2 10 Dec 2021 644.6 334.1 v high 193%

Notes

The Seasonal climate summary, generally published on the first working day of each month, lists the main features of the weather in Greater Sydney 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 Sydney “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 3 pm on Tuesday 1 March 2022. 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