Australian Weather

Today, 1:28AM UTC

The temperature in Melbourne looks set to hit the 30-degree mark for the first time since March, with maximums of 30°C forecast for both this Thursday and Friday. Melbourne’s warmest spring day to date in 2026 was 28.5°C on September 20. So far this month, Melbourne's average maximum has been 20.9°C, which is 1.2°C above the long-term average of 19.7°C. While October has been warm overall, Melbourne has seen no significant heat spikes, especially compared to Sydney's 34.8°C day on October 12. This week's pair of 30-degree Melbourne days won't be extreme in a month where the highest temperature in well over 100 years of records was 36.9°C, but it's a reminder that summer is on the way. As is often the case with both cold and warm spells in Melbourne, Adelaide gets a taste first, and that will be the case this week with the SA capital expecting a top of 31°C on Thursday. What is causing the warmth? Image: Predicted maximum temperatures across Australia on Tuesday, October 20, 2026, according to the ECMWF model. Source: Weatherzone. A very slow-moving high pressure system located over the Tasman Sea is causing northerly winds which are funnelling warm air from Australia's interior towards the country’s southern and southeastern states. The image above shows areas of intense heat (the pink zones) in Western Australia's Pilbara and Kimberley regions, where the mercury reached 44.8°C on Monday at Mandora Station in the western Kimberley. Some of that heat is tracking all the way southeast across the continent, including to Tasmania. Meanwhile the east coast is under the influence of a moist, onshore flow which is moderating daytime temperatures. That's why Hobart is currently about halfway through a potential eight-day run where its maximum is exceeding Brisbane's. Spring see-saw kicks in after warm spell Image: Mean sea level pressure and 850 hPa temperatures showing much cooler air establishing over SE Australia early on Monday, October 26, 2026. Source: Weatherzone. After Melbourne's warmth on Thursday and Friday, an in-between day is expected on Saturday with a maximum around 24°C as showers increase in a rain band ahead of an approaching cold front. Melbourne's classic "spring temperature see-saw" will then reappear, with maximums of just 16°C and 15°C currently predicted for Sunday and Monday respectively. At this stage, Monday looks like a chilly one right across southeastern Australia, with snow forecast for elevated parts of Tasmania and the mainland high country.

19 Oct 2026, 3:38AM UTC

An unusually slow-moving high pressure system centred over the Tasman Sea will cause a contrasting mix of weather across Australia this week, with heavy rain and thunderstorms in the country’s east and a spring heatwave in parts of the south. Air flows in an anticlockwise direction around high pressure systems in the Southern Hemisphere. As high pressure systems are often large and slow moving, this anticlockwise flow can control weather conditions for several days, sometimes more than a week. A large high pressure system will linger above the Tasman Sea this and remain near-stationary from now until the weekend. Computer models predict that the centre of this system will only move by about 500 km between Monday and Saturday. This is unusually slow of a large-scale weather system. Image: Modelled mean sea level and precipitable water at 11 am AEDT on Monday, October 19, 2026, showing a high pressure system centred above the Tasman Sea. Image: Modelled mean sea level and precipitable water at 11 am AEDT on Friday, October 23, 2026, showing the same high pressure system still centred above the Tasman Sea. A high pressure system centred over the Tasman Sea typically causes the following weather in Australia: Onshore winds over eastern Australia, which often enhance rain and thunderstorm activity over parts of Queensland and NSW. Northerly winds over southern Australia, allowing warm inland air to flow towards the country’s southern and southeastern states. Hot conditions in northwestern Australia. This week will feature all three of the features listed above and because the high will be near stationary for around six days, the weather will be repetitive from day-to-day for many areas in eastern and southeastern Australia. Rain and thunderstorms in eastern Australia Widespread showers and thunderstorms will affect parts of Queensland and NSW every day this week. There are signs that a two-day period of heavy rain could develop over southeast Queensland and northeast NSW on Thursday and Friday as an upper-level trough crosses the region. As this burst of heavy rain could occur during a prolonged period of wet and stormy weather, there would be a heightened risk of flooding if forecast rain totals eventuate. Some computer models predict that parts of southeast Queensland and northeast NSW could see 100 – 200 mm of rain this week. If this happens, it would be equivalent to roughly two months of October rainfall in some areas. Showers and thunderstorm activity will also affect parts of every other state and territory in Australia this week. This will partially be caused by the moisture being pushed towards Australia from the east by the high over the Tasman Sea, but also in response to moisture-laden air flowing over Australia from the Indian Ocean. Warmer-than-average sea surface temperatures in the Tasman Sea and Indian Ocean will also contribute to this week’s widespread rainfall in Australia. The map below shows how much rain one computer model is predicting across the country this week. This is not likely to be exactly how it will play out, but it gives a good indication of where the heaviest rain is currently expected to occur, and how widespread rainfall could be across Australia. Image: Forecast accumulated rain during the 7 days ending at 11 pm AEDT on Sunday, October 25, 2026. Source: Weatherzone. Hot air spreading towards southern Australia Northerly winds on the western flank of the Tasman Sea high pressure system will draw warm air from central Australia towards the country’s south and southeast this week. This weather pattern will create a unique situation where Hobart’s daily maximum temperatures will be higher than Brisbane’s maximums for much of the week. This is unusual became Hobart’s average maximum temperature in October is 10°C cooler than Brisbane’s. Image: Forecast temperature anomaly at 11 am AEDT on Thursday, October 22, 2026. Source: TropicalTidbits.com. Melbourne is forecast to have its first 30°C days of spring this week, while Hobart is forecast to reach the mid to high twenties every day from Monday to Friday, well above the city’s October average maximum temperature of 17°C. More extreme heat will occur in northwestern Australia at the start of this week as a hot air mass sits over the north of WA on Monday and Tuesday. As of 11 am AWST on Monday, temperatures had already reached as high as 44.6°C at Mandora. When will the weather pattern change? The high pressure system centred over the Tasman Sea is expected to move to the east of New Zealand from Sunday into early next week. This departing high is expected to make way for a cold front to sweep across southern Australia, which will likely cause another burst of rain and storms over large parts of the Australian continent from Sunday into early next week. There are even early signs that cold air could bring a dusting of spring snow to parts of southeastern Australia around Monday next week if enough cold air accompanies the front.