Sydney set for soaking with half the monthly average rainfall forecast
Sydney could receive more than half the average March rainfall in a day, with up to 70 millimetres of rain forecast for Thursday.
The heaviest rainfall is most likely to hit in the afternoon and evening in expected thunderstorms, the Bureau of Meteorology says.
The weather bureau has forecast between 25 and 70 millimetres of rain for Thursday, expected to mostly affect coastal suburbs.
Duty meteorologist Dmitriy Danchuk said there will be rain in the morning, but most of Thursday's rain is forecast to fall during thunderstorms in the afternoon and evening.
"There could be brief outbursts of heavy showers and that would continue for a couple of hours until late morning," he said.
"Then there could be some gap, followed by thunderstorms developing during the afternoon and we could get most of the rainfall today effectively from thunderstorms during the later hours."
While Mr Danchuk said Sydney could experience half the monthly average amount of rainfall, the chance of receiving 70 millimetres of rain is 25 per cent. The chance of 25 millimetres of rain falling is 50 per cent, he said.
The monthly average rainfall for March recorded at Observatory Hill is 130.8 millimetres. The highest monthly rainfall total for March is 521.4 millimetres recorded in 1942, and the lowest monthly rainfall for March was a mere 8.4 millimetres in 1964.
Thursday's rain forecast comes after parts of Sydney received almost 50 millimetres of rain on Wednesday, Mr Danchuk said.
"In the city we had just six millimetres, but the far northern beaches [saw] falls between 20 and 50 millimetres," he said.
Mr Danchuk said Thursday's rainfall event will extend into Friday with "solid rainfall numbers," before rain eases through Saturday and Sunday.
Sydney is forecast to receive between 15 and 45 millimetres of rain on Friday, with a chance of a thunderstorm in the morning and afternoon. On Saturday and Sunday there is a chance of showers, with up to six millimetres of rain.