Sydney Briefly Australia's Hottest Spot Amid Rare Heat Event
Sydney Airport recorded a temperature of 35.3°C at 11:50 AM on Wednesday, February 18, making it the hottest location in Australia at that specific time. This occurrence is notable as Australian capital cities do not frequently register the country's highest temperature.
Capital cities rarely claim Australia's highest temperature, making Sydney's brief top spot a significant event.
A previous notable instance occurred on January 4, 2020, when Penrith in Western Sydney reached 48.9°C. This particular recording was the highest temperature globally on that day and remains the highest for an Australian capital city's urban or suburban weather station.
Factors Contributing to Sydney's Heat
Four primary factors contributed to Sydney briefly experiencing these unusually high temperatures:
- Broad-scale Weather Pattern: The Sydney basin was positioned to receive hot northwesterly winds originating from the continent's interior. This occurred just before a cool change, which had already affected Victoria and parts of western and southern New South Wales, was due to arrive.
- Foehn Effect: Weatherzone meteorologist Ben Domensino explained that descending westerly winds on the eastern side of the Blue Mountains caused air to heat up due to the Foehn effect.
- Urban Heat Island Effect: Domensino also noted that the Greater Sydney region's built-up landscape warmed more rapidly compared to the surrounding vegetated areas.
- Time Differential: At that moment, it was early morning in Western Australia, where numerous locations were forecast to exceed 40°C later in the day. Other areas in Queensland, the Northern Territory, and northern South Australia were also warming at a slower rate but were expected to surpass Sydney's maximum temperature later in the day.
Cool Change and Forecast
Following the peak heat, several Sydney suburbs reached 36°C, with temperatures exceeding 37°C at Sydney Olympic Park and Holsworthy shortly after 1 PM.
A southerly change reached Sydney's southern suburbs just before 2 PM and progressed northward. The impact of this change was swift and significant. For example, Bellambi in Wollongong recorded a peak of 34.5°C at 12:05 PM, which then dramatically dropped to 23.4°C by 12:30 PM as the cool change passed through.
While this change initially brought no significant showers, the potential for showers or storms existed in Sydney and surrounding areas later on Wednesday afternoon.