Australian Weather

17 Dec 2025, 4:04AM UTC

Heavy rain could engulf northern Australia next week, with signs the season’s first monsoon burst could arrive in northern Australia during the lead up to Christmas. What is the Australian monsoon? The monsoon refers to a reversal of winds over the Australian tropics, which cause moisture-laden air to flow over Australia form the north and northwest. These rain-bearing monsoon winds affect northern Australia in periodic bursts throughout the wet season, which runs from November to April. Australia usually sees about two to four active phases of the monsoon each wet season. Numerous computer models are predicting the monsoon to develop over northern Australia next week, which would be the first time we have seen an active monsoon phase over the country so far this wet season. On average, the monsoon onset at Darwin typically occurs in late December. Wet lead up to Christmas The prospect of an active monsoon phase in northern Australia from next week significantly increases the likelihood of widespread rain over parts of Australia in the coming weeks. The monsoon can also cause low pressure systems to form near northern Australia, which increases the potential for tropical cyclone activity if these lows form over, or move over open water. While there is still some uncertainty regarding the strength and timing of the impending monsoon, most models are showing signs of enhanced rain over parts of Queensland, the NT and northern WA from next week. The maps below show how much rain is being predicted over Australia during the next 10 days from three different computer models. They all anticipate heavy rain over parts of northern Australia during the second half of December, with areas of heavy rain also possibly extending further south into Qld. Image: Forecast accumulated rain during the 10 days ending at 11pm AEDT on December 26, 2025, according to the ECMWF model. Source: Weatherzone. Image: Forecast accumulated rain during the 10 days ending at 11pm AEDT on December 26, 2025, according to the ACCESS-G model. Source: Weatherzone.   Image: Forecast accumulated rain during the 10 days ending at 11pm AEDT on December 26, 2025, according to the GFS model. Source: Weatherzone. While the monsoon directly impacts northern Australia, it can also feed moisture into rain-bearing systems over other parts of the country. Weatherzone’s meteorologists will be keeping a close eye on the monsoon during the next couple of weeks and providing updates on its impacts on the Weatherzone news feed.

16 Dec 2025, 12:27AM UTC

A mass of hot air that saw Perth reach 40°C on Sunday will spread across Australia this week, causing temperatures to climb in Adelaide, Melbourne, Hobart, Canberra, Sydney and Brisbane, and everywhere in between. Hot in the west A high pressure system centred to the south of Australia has allowed a hot air mass to build over WA during the last couple of days. The heat was driven towards the west coast of WA on Sunday, causing Perth’s maximum temperature to reached 40.1°C. On Monday, Dalwallinu in the state’s Central Wheatbelt reached 40.9°C, while Morawa to the southeast of Geraldton hit 42.6°C. The heat will intensify and spread towards the south of WA on Tuesday and Wednesday. Large areas of southern WA will see temperature reaching the low to mid 40s over the next two days, possibly hitting 46°C to the north of Eyre on Wednesday afternoon. Image: Forecast maximum temperature on Wednesday, December 17, 2025. Source: Weatherzone. Heat spreading east The high pressure system will move over Bass Strait on Tuesday and out to the Tasman Sea from Wednesday, allowing the hot air to spread towards the east during the remainder of this week. South Australia will become progressively hotter between now and Thursday. Adelaide is forecast to reach around 35°C on Wednesday and 39°C on Thursday, making for two very hot days to start the Men’s Ashes Test at the Adelaide Oval. Temperatures will drop in the state’s south from Friday into the weekend as the heat becomes more confined to northern WA. Image: Forecast maximum temperature on Thursday, December 18, 2025. Source: Weatherzone. Victoria will heat up between now and Friday, with temperatures predicted to reach the low 40s in the state’s north on Thursday and Friday. Melbourne’s maximum temperatures are predicted to reach around 32°C on Wednesday and 37°C on Thursday, which would be the city’s hottest day in 10 months. Image: Forecast maximum temperature on Friday, December 19, 2025. Source: Weatherzone. Tasmania’s exposure to this warm air will be brief, with temperatures climbing to around 29°C in Hobart on Wednesday before cooling again by Thursday. The warmth will last a little longer in the state’s north, where Launceston is predicted to reach 26 to 29°C from Wednesday to Friday. Image: Forecast maximum temperature on Saturday, December 20, 2025. Source: Weatherzone. Hot air will linger over New South Wales and the Australian Capital Territory during the rest of this week, spreading towards the coast from Wednesday. Sydney is forecast to reach around 27°C on Wednesday and then 31 to 35°C for the rest of the week. Western Sydney could get close to 40°C on Friday. Canberra should also reach the low to mid-30s from Wednesday to Saturday. Image: Forecast maximum temperature on Sunday, December 21, 2025. Source: Weatherzone. Heat will build over southern Queensland late in the week, with Brisbane’s maximum temperatures climbing to the low to mid-30s from Friday. Thunderstorms This week’s heat will be accompanied by areas of rain and thunderstorms as moisture feeds into a low pressure trough on the western flank of the high pressure system. This wet and stormy weather will extend from northern Australia down through central Australia by Thursday, before spreading deeper into southeastern Australia from Friday into the weekend. Some of this week’s thunderstorms mare likely to become severe, with potential for heavy rain, large hail and damaging winds. Be sure to check the latest forecasts and severe thunderstorm warnings in your area during the rest of this week.