Heavy falls and possible thunderstorms could bring up to 120mm of rain for parts of coastal NSW

Authorities are asking the public to watch for hazardous driving conditions as areas south of Sydney, including the Illawarra could receive up to 100mm of rain. Photograph: Bianca de Marchi/AAP

Parts of coastal New South Wales could receive up to 120mm of rain over the weekend with heavy falls expected from late Saturday.

The rainfall comes 10 days after Sydney broke a century-old temperature record, with 184 days of temperatures exceeding 20C.