There's a medium (40%) chance of showers late this afternoon and evening and also the chance of a thunderstorm with little or no rainfall.

Winds will be northerly 20 to 30 km/h shifting cooler west to south-westerly 15 to 20 km/h in the afternoon.

At 6.30am it was 18.3 degrees in Warrnambool and felt like 13.3.

The city is expecting a top of 31 degrees, Hamilton 34, Colac 35, Ararat 37, Casterton 34, Mortlake 34, Heywood 31, Portland 27, Port Fairy 29, Terang 31 and Camperdown 31.

A high pressure system is centred over the Tasman Sea.

A low pressure trough crossing South Australia will move across western Victoria this afternoon, reaching central districts during the evening then will clear eastern parts on Tuesday morning.

Another high pressure system will develop south of the Bight on Tuesday and extend a ridge across southern Victoria on Wednesday and Thursday, with a weak cold front to cross Tasmania during Thursday.

For the week ahead it looks fine pretty fine and and mild, except for Saturday.

Tuesday we are back to a partly cloudy 14, Wednesday and Thursday 16, Friday cloudy 17, Saturday a 40 per cent chance of showers 17, Sunday 17 and Monday 19.

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