Millions of Australians are set to experience unseasonably warm weather this week as a significant high-pressure system directs hot air from the country's interior towards populated areas. This warm blast could lead to Sydney recording its hottest start to spring in more than half a century.
Sydney is forecast to reach highs of 24-27 degrees Celsius (75-81 degrees Fahrenheit) for the first three days of spring, which is 4-7 degrees Celsius above the seasonal average. The last time the city experienced three consecutive days above 24 degrees Celsius at the start of spring was in 1969. If the temperature on any of the first three days of spring reaches or exceeds 24.8 degrees Celsius, it would mark the warmest spring start in Sydney in 161 years. Further warming is expected over the weekend, with the city predicted to reach 29 degrees Celsius on Saturday and interiors potentially soaring into the 30s.
Other major cities are also expected to see above-average temperatures. Melbourne, Adelaide, and Hobart are forecast to record warmer-than-usual conditions on Tuesday. Canberra is predicted to hit 21 degrees Celsius on Wednesday, its highest mark for this time of year in five years. Brisbane could see temperatures climb above 30 degrees Celsius later in the week.
Computer modeling suggests that most regions of Australia, excluding the tropics, will experience above-average maximum temperatures throughout September. This warming trend is accompanied by predictions of drier-than-usual conditions for large parts of the country during the first month of spring.
This anticipated warmth follows a record-warm winter for several Australian cities. Sydney, Melbourne, and Canberra all registered their warmest winters on record, while Adelaide and Hobart experienced their second-warmest. Sydney recorded 186.2 mm of rain in winter, significantly below the average of 311 mm, contributing to its record-warm seasonal mean temperature of 15.27 degrees Celsius, approximately 2.25 degrees above the long-term average.
The absence of East Coast lows during Sydney's winter is cited as a contributing factor to the warmer days, as these systems typically bring cloud cover and rain that suppresses maximum temperatures.
