Up to 80mm of rain forecast to drench parts of Sydney on Thursday

Showers in Kogarah today had pedestrians reaching for their umbrellas. Rain is forecast to be heavier on Thursday.
Showers in Kogarah today had pedestrians reaching for their umbrellas. Rain is forecast to be heavier on Thursday.

Dust off the rain coats and umbrellas because Sydney is set for a good soaking with much of the NSW coast to cop a barrage of rainy days.

Heavy rain is expected to make landfall between the Illawarra region and the Central Coast about midday tomorrow, Thursday, with the heaviest falls forecast for Sydney in the afternoon.

In some forecast maps produced by the Bureau of Meterology, Sydney can expect to receive 50 to 80mm of rain as hot air from the northern regions makes its way south.

"There is a very high chance of showers, most likely in the afternoon and evening," the Bureau website forecasts. "There is also a chance of a thunderstorm in the afternoon and evening. Heavy falls are possible along the coastal fringe."

Sydney could receive more than half the average March rainfall in a day.

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.

Bureau meteorologist Elli Blandford said the rain was due to a coastal trough "which is pushing humid air down from the tropics, creating a moist atmosphere which increases precipitation.”

A maximum temperature of 24 degrees is forecast for Thursday.

Friday will remain wet, with the final edge of the trough likely to dump an additional 15mm of rain on the city in the morning.

Ms Blandford said residents concerned about rainfall levels should keep an eye on the BOM’s website and Twitter page, with multiple rainfall warnings expected to be made sometime tomorrow.

Sydney Airport received 3.2mm overnight while Lucas Heights received just 0.8mm of rain.