Warrnambool's State Emergency Service (SES) attended to 17 call-outs between 1pm and 2.30pm, with most cases involving trees blocking roads or fallen on rooftops.

Just before 1pm a gust tore apart the roof of the derelict Gunditjmara Aboriginal Co-Op at the Harris Street Reserve. 

Two Warrnambool properties had roof tiles blown off, while fallen trees partially or completely blocked road at Harlen Street, Breton Street, Hider Street and the Princes Highway at Allansford. 

A Norfolk Island pine also lost its branch to the wind outside the Warrnambool railway station, closing one lane of traffic for about 20 minutes while council workers secured the area.

The Koroit Kindergarten took some damage after a large tree fell on its roof at 1.20pm, while a shed at Mepunga also lost its roof.

It is believed at least three branches temporarily blocked Cobden-Warrnambool Road near the Laang Speedway.

Peak gusts up to 98km/h have been recorded at the Portland airport.

The SES has advised people to move vehicles under cover or away from trees, secure loose items around your house and keep clear of fallen power lines.

SES regional officer David Ralston, based at the Hamilton regional headquarters, said there had been a dozen jobs this morning around the south-west.

"It's a bit windy and wet and we've had a few jobs, particularly in the Portland area. We've had three or four call-outs around Portland with some flash flooding and trees down," he said.

"They've had a heavy shower with some water inundation due to blocked spouts. We're continuing to monitor the situation and keep a close eye on things.

"By late this afternoon the most severe weather will have passed through."

The SES was called to respond to situations at Portland, Dartmoor and Warrnambool this morning.

Warrnambool SES controller Giorgio Palmeri said a Warrnambool crew was dispatched to a fallen tree at Rollos Road, Nullawarre, about 9am.

He said the tree was blocking the road.