TORONTO -- Environment Canada has issued a rainfall warning for the city of Toronto ahead of a rare and intense weather system expected to significantly impact southern Ontario this weekend.

"Persons in or near this area should be on the lookout for adverse weather conditions and take necessary safety precautions," the warning reads.

The warning follows a special weather statement issued by the organization Friday morning for all of southern Ontario, warning of heavy rain, strong winds and freezing rain.

In the Greater Toronto Area, 40 to 60 mm of rain is anticipated before Sunday evening. 

"This is a complex a storm system," CTV News Toronto weather specialist Anwar Knight said Friday. 

"Part of the problem with the rain is that the ground is frozen and there is no place for it to go. There could be flooding."

Knight said the rain is forecast to transition to freezing rain in the GTA on Saturday afternoon.

"It could be an eight-to-12 hour event of freezing rain," Knight said. "Many places in southern Ontario could get a months' rainfall in 24 hours. This is a pretty intense storm. It's very rare."

Full list of weather alerts for southern Ontario 

ice storm

Several hours of freezing rain are also forecast to occur in Guelph, Waterloo, Kitchener and Cambridge after the temperature dips below the freezing mark on Saturday, Environment Canada says.

Winds gusting up to 70 km/h are expected Sunday morning in the region, with the highest gusts occurring along the shores of Lake Huron. 

“This scenario is expected to result in significant ice accretion over these regions,” Environment Canada said. “Strong winds coupled with ice build-up on tree branches and power lines could cause power outages in the hardest hit areas.”

Meanwhile, areas north of Toronto like Barrie, Orillia, Midland and Collingwood are also expected to be hit hard by the storm. 

Similar warnings are also in affect for areas east of Toronto. 

Environment Canada says travel will be impacted across southern Ontario Saturday and Sunday. 

City of Toronto preparing for storm

The City of Toronto says their "storm readiness plan" is in place and crews will be available around the clock for assistance. 

"The City undertakes regular inspections, cleaning and maintenance of more than 10,000 kilometres of sewer pipes to ensure that the system operates well and has long-term capital plans to help alleviate basement flooding," the city said in a news release.

"Transportation Services staff are ready to support the storm response by monitoring conditions on roadways and actively patrolling roads to clear debris and keep catch basins clear."

Meanwhile, the Toronto and Region Conservation Authority said the storm will create potentially flooding and hazardous conditions.

"The combination of slippery and unstable banks could create hazardous conditions close to any river, stream or other water body. All shorelines, rivers and streams within the GTA should be considered hazardous." 

For the latest information, visit our weather page.