Nearly half of Australia is under a flood watch as several states and territories brace for heavy rainfall in the coming days.

A slow-moving tropical low-pressure system hovering over central Australia is fueling these conditions, leading to severe weather alerts across a region comparable in size to France and Belgium.

The Northern Territory, Victoria, South Australia, Queensland, and New South Wales are expected to experience the most significant impact starting today.

Jonathan How, a senior meteorologist at the Bureau of Meteorology, advises residents to prepare for sustained rainfall.

“In the Northern Territory and Queensland, the rain might begin to ease from Wednesday into Thursday. However, for South Australia and New South Wales, heavy rain is expected to persist through the weekend, potentially extending further south into South Australia by Friday,” How explained.

In New South Wales, authorities are alerting residents in the western part of the state to ready themselves for the severe weather conditions commencing today.

Residents in Tibooburra, Broken Hill, Wilcannia, White Cliffs, Wanaaring and Menindee are advised to stay indoors during severe weather and avoid unnecessary travel.

Rainfall totals of 50mm to 90mm are forecast within 24 hours, with isolated falls up to 130mm possible. In some areas, much of this rain may fall within six hours, increasing the likelihood of rapid creek rises, overland flooding and dangerous driving conditions.

In Victoria, a severe weather warning has been issued for a large area east of Melbourne, including the west and south Gippsland.

From tomorrow, some breaks in the rain are forecast across the NT and Queensland, but damp conditions will continue to build across parts of South Australia and north-western pockets of New South Wales.

Heading into Friday, the rain could extend into central parts of South Australia, including Adelaide.

The wet conditions are likely to linger over Central Australia into the weekend, and possibly continue into next week.

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