A major trough has been bring wild weather and flash flooding to south-east Queensland, but good falls have also been recorded at inland agricultural areas.

According to WeatherZone, since 9am yesterday Redcliffe, north of Brisbane, has received more than 140mm, while inland Roma has received 28mm, St George 45mm, Dalby 28mm, Miles 25mm, Oakey 48mm, and Toowoomba 19mm.

Further north Maryborough has received 42mm, Kingaroy 29mm, Gympie 38mm and Gayndah 26mm.

Since the rain started falling on Monday evening, more than 170mm has fallen at Beerburrum, on the Sunshine Coast, the most rain they've had in such a short time in six years.

This is also one-and-a-half times the monthly average and there's more to come, according to WeatherZone. However, rain on the Sunshine Coast is likely to ease later today as a low pressure trough takes the focus south to the Brisbane, Gold Coast, eastern Darling Downs and nearby New South Wales.

These areas will be in for flooding, possibly major flooding over the next few days with totals exceeding 200mm.

There's even potential for 300mm or more in some places by the weekend, when rain starts to clear.

In NSW overnight there were falls of up to 20mm on the north coast, while further west Gunnedah has received 15mm, Moree 21mm, Narrabri 18mm, Walgett 17mm, Coonamble 23mm, Bourke 23mm and Cobar 23mm.

In the west WeatherZone says the Lower Western and Southwestern districts of Western Australia are getting ready for the best rain in almost a year.

Yesterday the odd shower or two fell in the wake of weak cold front, but they were indicators of the approaching rainfall surge.

Today, showers and isolated storms will develop, but this will only be the birth pains.