More wild weather is continuing to lash Victoria, with showers and thunderstorms across large parts of the state.
A severe thunderstorm warning issued by the Bureau of Meteorology just after 12:30pm warned of damaging winds and heavy rainfall accompanying a cluster of storms.
Locations that may be affected over the next few hours include Melbourne, Geelong, Ballarat, Frankston, Bacchus Marsh and Rosebud.
A more specific warning has also been issued warning of a thunderstorm soon to impact the western parts of Greater Melbourne.
Thunderstorm cells tore through much of Melbourne and parts of regional Victoria on Thursday, and thousands of people remain without power across the state.
At 10:11am today a wind gust of 133 kilometres per hour was recorded at Mount Gellibrand in the Otways.
More than 5,000 premises are still experiencing power outages, with the west of the state worst affected.
Energy distributor Powercor had more than 20,000 outages at one point late on Thursday.
The west of the state was hit again late on Thursday and overnight into Friday, with Geelong experiencing flash flooding overnight.
The State Emergency Service (SES) said there were about 750 calls for assistance across Victoria in the 24 hours to 8am.
A day after lightning storms started small fires, the town of Edenhope in the state's Wimmera region was hit by storms that tossed trampolines, brought down trees and ripped the roof off a house.
"There is every chance storms will occur again, and if that happens outages might be possible."
About 450 of the calls to the SES were overnight.
The busiest unit was in South Barwon, with nearby Geelong and Sorrento on the Mornington Peninsula also experiencing a high number of calls.
The Bureau of Meteorology said the wild weather was likely to be repeated into Friday, and the SES was bracing for more callouts from around noon.
Senior forecaster Mark Anolak said the day would be warm to humid, but conditions were expected to ease over the weekend.
"[On Friday], we still have a very tropical air mass over the state," he said.
"And, in some cases, some of those showers and thunderstorms could be quite heavy, producing some localised flash flooding."
SES deputy chief officer Alistair Drayton told ABC News Breakfast one of the biggest concerns of the organisation was "some of the poor choices people are making in relation to driving through water".
"We had a significant number of in-water rescues overnight, particularly around the south-west and Geelong area."
Mr Drayton said the SES had received help from other emergency agencies to respond to the high volume of calls on Thursday and into Friday.
Business owners left mopping up
Callum Macpherson, who owns a bottle shop in Geelong, went to check on his business as storms swept through on Thursday evening.
"We were quick to act but the water had already got in through the front doors," he said.
"We had a bit of a clean up to do."
He said the water came up to ankle height.
Mr Macpherson said his store had flooded three times during storms over the past six years, which had prompted him to purchase sandbags.
"Previous storms we've experienced here we've had stock on the floor, leather couches, rugs, which we've since taken out of the shop," he said.
"Everything's above the flood level now.
"We've adapted our store to deal with these one-in-100-year storms that are happening more and more regularly."
Other stores, including a beauty business in the Geelong suburb of Belmont, did not fare so well.
Tash, who owns Lash Baby, found the ceiling of her business had collapsed and has a huge clean-up ahead.
Cool change for Melbourne over the weekend
Mr Anolak said conditions were expected to ease during the weekend in parts of Victoria.
"The main showers and thunderstorms move to the east of the state," he said.
"So the north-east ranges in Gippsland are likely to continue to receive showers and thunderstorms.
It has been a sweltering week for much of the state, with temperatures well over 30 degrees Celsius in Melbourne every day and warm and humid nights.
Mr Anolak said Melbourne could expect to reach a high of 25C on Saturday and a top of 29C on Sunday, with more warm weather to come next week.
"There will be one or two showers Saturday morning … but the afternoon should be fine, and Sunday should be fine," he said.
On Thursday, lightning sparked hundreds of small fires across the state, with three residents from Melbourne's northern suburbs taken to hospital after their home caught alight.
Meanwhile, Mildura, in the state's north, had its wettest January day ever, with 80mm of rain recorded in the 24 hours to 9am Thursday.
Yesterday, Bureau of Meteorology's Diane Eadie told the ABC the influence of La Niña had resulted in the summer storms bringing much more moisture than those in previous seasons.
