Record 32.1C heat, extreme fire danger; cool change sweeps in with winds gusting above 100km/h
Sydney appeared to be in the grip of summer at the very beginning of spring. On Saturday, temperatures reached 32.1C, breaking the record for the highest temperature recorded this early in September in the city. The intense heat, combined with dry and gusty winds, heightened the risk of bushfires and prompted an extreme fire danger warning. But before the heat of the day had fully subsided, the weather changed dramatically — cooler air moved in during the evening, accompanied by wind gusts of more than 100km/h.
Since temperature records began in 1859, Sydney had never exceeded 32C this early in September. At 2:33pm on Saturday, the temperature at Sydney’s Observatory Hill reached 32.1C. It was the earliest point in the season that Sydney had climbed above 32C. Previously, the earliest September 32C readings had occurred on September 13, in both 2009 and 2017.
Temperatures rose to between 30C and 33C across almost all parts of the city. In western Sydney, Penrith climbed above 33C. Dry and gusty westerly winds pushed warm air across the city, making the unusual heat felt even in coastal areas.
Record warmth over four days
Saturday’s record temperature was the culmination of an unusually warm four-day spell. Over those four days, the average maximum temperature at Observatory Hill was 27.93C — about 8C above the long-term average for early September.
That average also set a new record for Sydney’s warmest four-day period this early in September. During the first few days of spring, temperatures in the city reached levels more typical of the middle of summer.
Bushfire fears rise with the heat
The dry and strong winds made the situation even more dangerous. Humidity fell to around 20 per cent in parts of Sydney, increasing the risk that fires could spread rapidly through dry grass and bushland.
Greater Sydney was placed under an extreme fire danger rating on Saturday. A total fire ban was imposed and remained in place until midnight. Residents were urged to comply strictly with restrictions on lighting fires.
Bureau of Meteorology senior meteorologist Jonathan How said a powerful weather system sweeping across south-east Australia had created a combination of heat, damaging winds, rain and flood risk. Fire danger in Sydney had reached an extreme level.
Weather changes within hours
As Saturday afternoon progressed, however, the weather began to change rapidly. A strong cold front moved across south-east Australia towards Sydney. Warm west to north-westerly winds began giving way to cooler west to south-westerly winds.
Meteorologist Jonathan How said the hot weather would not last long. The cool change would move north along the coast, with temperatures in Sydney expected to fall rapidly.
By 10:30pm on Saturday, the temperature at Observatory Hill had fallen to 20.5C. That meant temperatures had dropped by almost 12C from the afternoon’s record high of 32.1C.
Winds gust to 113km/h
Although temperatures fell, the danger from strong winds had not completely passed. Gusts of more than 100km/h were recorded in several parts of New South Wales on Saturday.
The strongest gust reached 113km/h at Penrith Lakes, while gusts of 104km/h were recorded at Moss Vale and Cabramurra, and 96km/h at Sydney Airport.
Severe weather warnings for Sydney and the Illawarra were cancelled by the evening, but damaging winds remained possible across parts of the Snowy Mountains, southern ACT, the South Coast, Central Tablelands, Hunter and Mid North Coast.
Rain, thunderstorms and flood risk
The powerful cold front affected more than New South Wales. Parts of Victoria, Tasmania and South Australia experienced rain and thunderstorms, while flood warnings were issued for northern Victoria and Tasmania.
Snow and blizzard conditions were also possible in alpine areas of southern Australia. While some areas faced intense heat and bushfire danger, other regions were dealing with cold weather and the prospect of snow — creating a striking contrast across Australia’s weather system.
Relief for Sydney from Sunday, heat lingers further north
The cool air moved to north on Sunday, bringing much milder conditions to Sydney. However, warmer weather will persist for a time across northern parts of New South Wales and south-east Queensland.
Saturday began in Sydney with a 167-year record for early-season heat and ended with a sharp cool change and damaging winds. The dramatic swing in weather at the very beginning of spring has once again highlighted the growing risk of extreme weather across Australia.
