Australian Weather

23 Dec 2025, 9:39PM UTC

The monsoon has developed over Australia for the first time this season, prompting flood watches in parts of the Northern Territory and Queensland over the Christmas period. The monsoon refers to a reversal of winds over the Australian tropics, where the dry east or southeasterly winds that prevail for much of the year are replaced with moisture-laden winds from the 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. Image: Typical wind patterns and associated rainfall impacts during an active monsoon phase in northern Australia. Source: Weatherzone. Northwesterly winds have started flowing over northern Australia this week, marking the arrival of the Australian monsoon for the first time this wet season. As a result, some areas of the NT’s Top End received more than 100 mm of rain during the 24 hours ending at 9am on Tuesday, including 135 mm at Murganella Airstrip. The satellite images below show vast areas of cloud flowing over the country’s northern tropics on Tuesday, revealing the monsoon arriving for the first time this wet season. Image: Visible satellite images captured by the Himawari-9 satellite on Tuesday, December 23, 2025. Source: Weatherzone. The average monsoon onset date for Darwin is around December 28 to 29, so the monsoon arriving by the middle of this week is slightly earlier than usual. Rain is likely to become heavier and more widespread over the NT and Qld during the remainder of this week and will likely continue into early January. Flood watches have been issued for parts of the NT and Qld and flood warnings are likely to follow as the rain starts to fill rivers. This rain event may cut off outback roads in the coming one to two weeks, with heavy rain also expected to extend towards eastern Qld between Christmas and New Year’s Eve. Be sure to check the latest flood watches and warnings in the coming days and weeks for the most up to date information in your area.

23 Dec 2025, 4:36AM UTC

Tropical cyclone Grant has formed over the Indian Ocean to the northwest of Australia, becoming the second system to be named inside the Australian region so far this season. Grant became a category one tropical cyclone early on Tuesday morning when it was located roughly 395 km to the east of the Cocos (Keeling) Islands. The tropical cyclone is forecast to gain strength as it moves towards the west over the next few days. Computer models suggest it will pass close to or over the Cocos (Keeling) Islands on Wednesday (Christmas Eve) or Thursday (Christmas Day), most likely as a category two system. Based on its current forecast track and strength, Grant could cause damaging to destructive winds with gusts of up to around 130 km/h, along with heavy rain and abnormally high tides over the Cocos (Keeling) Islands on Wednesday or Thursday. The islands have a population of around 600 people. Image: Enhanced infrared satellite image showing Tropical Cyclone Grant to the east of the Cocos (Keeling) Islands on Tuesday. Source: Weatherzone. After passing the Cocos (Keeling) Islands, Grant is expected to continue moving towards the west over the Indian Ocean, away from the Australian mainland and its external territories. Some forecast models suggest it could travel all the way across the Indian Ocean and track towards Madagascar in early January, a path somewhat similar to Tropical Cyclone Freddy in 2023. Tropical Cyclone Grant is the second system to be named in the Australian region so far this season, and the season’s third tropical cyclone to move through the Australian region. It follows Tropical Cyclone Bakung, which formed near Indonesia earlier this month before entering Australia’s area of responsibility, and Tropical Cyclone Fina, which impacted the NT and WA in November. The next tropical cyclone to form inside Australia’s area of responsibility will be named Hayley.