Monday, 2 March 2020 - Seasonal Climate Summary for Greater Sydney - Product code IDCKGC25L0

Greater Sydney in summer 2019-20: warm, but wetter than average after a dry start

Greater Sydney experienced a warm summer with mean minimum and maximum temperatures being above average throughout. After a very dry start to the season, February was particularly wet and resulted in above average summer rainfall totals. Smoke and raised dust resulted in poor air quality across the region for much of December and January.

A wet end to summer

• After a dry start to summer in December and January, overall summer rainfall in 2019-20 was above average across Greater Sydney
• December and January both had below average rainfall, however February had very much above average rainfall throughout; it was the wettest February since 1956 in the Blue Mountains, and since 1990 or 1992 elsewhere
• A coastal trough from 7 to 10 February brought particularly high rainfall to the region resulting in many sites having their highest summer daily rainfall on record
• Some sites had their highest total summer rainfall on record and other sites had their highest total summer rainfall for at least 20 years

Warm days and nights

• Daytime temperatures in summer across Greater Sydney were generally one to two degrees warmer than normal
• December and January were particularly warm with several new records being set for hot days
• 4 January was especially hot, with most sites reaching the mid 40s and some sites having their highest temperature on record; Penrith Lakes reported 48.9 °C on this day, the highest temperature ever measured in the Sydney basin and the hottest recorded in New South Wales this summer
• Daytime temperatures in February were closer to average, with coastal sites being slightly warmer than average and inland and Blue Mountain sites being slightly cooler than average
• Minimum temperatures were generally around a degree warmer than average for summer
• Summer started off with relatively cool overnight temperatures and Canterbury equaled its lowest summer temperature on record on 3 December
• Warm nights at the start of February saw some sites, including Penrith Lakes, Badgerys Creek, Horsley Park and Mount Boyce, recording their warmest summer night on record

Sydney (Observatory Hill)

• Total rainfall for Sydney (Observatory Hill) was 514.6 mm, which is 173% of the long-term average of 297.7 mm and the wettest summer since 1991/1992
• During the February rain event, Sydney (Observatory Hill) had 242.0 mm rain in two days and 391.6 mm in four days, the highest such totals since 1992 and 1990 respectively
• The mean daily maximum temperature for Sydney (Observatory Hill) was 27.3 °C, which is 1.6 °C above the long-term average of 25.7 °C, and the eighth-warmest summer on record
• The warmest day was 41.3 °C on 23 Jan, and the coolest day was on 1 Dec when the temperature reached 22.0 °C
• The mean daily minimum temperature for Sydney (Observatory Hill) was 20.0 °C, which is 1.6 °C above the long-term average of 18.4 °C and the equal eighth-warmest summer on record
• The coldest morning was 14.1 °C on 3 Dec, and the warmest morning was on 2 Feb when the minimum temperature was 24.8 °C

Other phenomena

• Bushfire smoke and raised dust affected the Sydney basin for much of December and January, with poor air quality being a significant feature of the summer
• Raised dust fell as dirty brown rain over the Sydney basin on 24 January
• Heavy rain from 7 to 10 February resulted in flooding in the Hawkesbury-Nepean Rivers and local flooding in various parts of Greater Sydney. There was also some coastal erosion on beaches. Observatory Hill had 242.0 mm rain in two days and 391.6 mm in four days, the highest such totals since 1992 and 1990 respectively

Extremes Maps Records Summaries Important notes the top

Extremes Maps Records Summaries 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 Important notes the top

Extremes Maps Records Summaries Important notes the top