Sunday evening's deluge of rain caught some drivers unawares. Credit:Arsineh Houspian A State Emergency Service spokeswoman said more than 200 calls were received on Sunday evening. More than 100 of those calls were for flooding, and 75 for building damage. "We haven't had any reports of over-floor flooding at this stage," she said. "Most are for dripping roofs; some are concerns about their roofs collapsing or for flooded garages." Melbourne's inner south-west was hardest hit, along with Geelong, Sorrento and Frankston, the SES spokeswoman said. "We've also had a couple of calls from Phillip Island and the mid-west, including Ballarat. And it's now starting to extend into Glen Eira and Knox."

The power of the storm was obvious as it rolled in over Melbourne's outer east. Credit:Nathan Edwards By 11pm, power had been restored to most Victorian homes. Power pole fires were responsible for some of the outages, while 1500 homes were in darkness because bark blew onto a powerline in Trentham Road, Tylden. Lightning forced the Demons and Lions players into an early half-time break. Credit:Michael Dodge Cinema-goers were disappointed when Readings Cinemas in Waurn Ponds was forced to close on Sunday evening due to storm damage.

And commuters were left to find another way home when the Sandringham line was suspended between Flinders Street and Sandringham due to flooding over the tracks. Thunderstorms are expected to hit the city. Credit:Chris Hopkins Tram routes 12, 96 and 109 were similarly delayed because of flooding at the Clarendon Street junction, Docklands, where the three routes converge. Earlier on Sunday, lightning strikes temporarily suspended an AFLW match at Cranbourne, forcing the Demons and Lions players into an early half-time break. Melbourne is is set for the wettest night this year. Credit:Wayne Taylor

Officials told players to retreat to the rooms after thunder and lightning erupted at Casey Fields. Play resumed about 10 minutes later. Senior forecaster Rod Dixon said the mercury reached 30.7 degrees at 3.30pm Sunday and started to plummet about 5.45pm from 28 degrees to 23 degrees. A firebomber tackles the Diggers Rest grassfire on Saturday. Credit:Chris Hopkins

"The rain has dropped it further to 20 degrees in the city," he said. "We're forecasting a minimum of 16 degrees and a top of 19 for Monday so we'll see a fairly gradual decrease overnight and a fairly cool day with light southerly winds." The wettest day of 2017 so far was the 24 hours to 9am on January 20, when the city received 22.6 millimetres. "We could eclipse that if we do get some of those thunderstorms over Melbourne," Mr Efron said. "But it does look particularly wet across central Victoria, as well as into elevated parts of Gippsland.

"As well as the rainfall, we could see some thunderstorms tonight, as well across a lot of the state." Despite the forecast, ticketholders to Melbourne Zoo's twilight concert tonight were told the show would go on. Umbrellas, however, were banned. The email alert recommended people bring waterproof tarps instead. The rainfall was a welcome relief for emergency services, which responded to a series of bushfires across Victoria this weekend. A fire at Diggers Rest on Melbourne's north-west fringe threatened homes and burned near the Organ Pipes National Park.

Inquiries by fire investigators into the cause of the fast-moving grassfire have established that it was ignited by a ride-on lawnmower. CFA state duty officer Jamie Hansen said the blade assembly of the lawnmower "malfunctioned and created a spark. The mower was mechanically unsound". The fire, which broke out about 11.20am, burnt about 110 hectares and had a perimeter of eight kilometres. It was tackled by 170 firefighters, 33 firefighting vehicles and four aircraft. "We had gusty north-westerly winds, and that, coupled with difficult terrain and the gullies in the area, [meant] we had quite erratic fire behaviour, which made it very difficult to control," Mr Hansen said. "It was brought under control at six o'clock last night, and then early this morning we've declared it safe.

"There's been no loss of homes in the area. There were a few homes that had superficial damage, and there's obviously a lot of fencing that has been destroyed." Mr Hansen said the grassfire was a prime example of the kind of threat grassfires could pose this summer "with the weather conditions the way they've been. The fuel in the grassland areas has increased significantly this season." Authorities responded to two other grassfires on Sunday, including one at Tooradin, south-east of Melbourne. Authorities said the fire was under control about midday on Sunday. The fire burnt about four hectares. "It was caused by a stolen car left in a paddock and set alight," Mr Hansen said. In the Latrobe Valley, fire crews responded to a grassfire at Hazelwood North. The fire, which is being treated as suspicious, was quickly brought under control.

The thunderstorms expected to hit Victoria late on Sunday could bring lightning strikes, but the expected heavy rain will reduce the risk of fires caused by any possible strikes.