It's expected to bring a cool change to the south-west later this afternoon with showers expected and possibly storms.

Rain is also forecast for Saturday.

Earlier: Today across the south-west will be cloudy with a very high (90 per cent) chance of showers, most likely during this afternoon and early evening.

Light winds will become south-westerly 15 to 25 km/h in the early afternoon then tend southerly 20 to 25 km/h in the evening.

There's a strong marine wind warning for the west coast.

In addition to all that the McDonald Restaurant in central Warrnambool will not have drive-thru access for a couple of hours this morning.

A worker tell us that electrical boxes are being replaced so you have to go into the restaurant to get service.

Pity you had to get right to the drive-thru to work that out.

Warrnambool is expecting a top of 21 degrees, Hamilton 21, Colac 21, Ararat 23, Mortlake 21, Heywood 20, Portland 19, Port Fairy 21, Terang 18 and Camperdown 18.

A high pressure system is centred over the Tasman Sea as a low pressure trough develops over the Bight and a cold front moves crosses the Southern Ocean.

The trough and front will move steadily eastwards today, with the front crossing western and central Victoria later in the day before clearing to the east early Friday morning.

The trough is expected to linger over northwest Victoria on Friday as a high moves rapidly eastward across Tasmania.

A low is likely to develop on the trough during Saturday and move eastwards across Victoria, reaching the Tasman Sea on Sunday.

For the week ahead, Friday will be mostly sunny 17, Saturday showers 14, Sunday partly cloudy 13, Monday partly cloudy 14, Tuesday partly cloudy 17, Wednesday partly cloudy 18 and Thursday partly cloudy 19.

So, there's a 90 per cent chance of between two and five millimetres of rain today, just a 30 per cent chance of rain Friday, a 70 per cent chance of between 3-6mm on Saturday and a 80 per cent chance of between 0-2mm on Sunday.

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