Most of southern Ontario including the GTA is bracing for significant rainfall starting Tuesday night that could cause localized flooding in some areas.

Environment and Climate Change Canada has issued a special weather statement for a system expected to bring between 20 to 40 millimetres of rain. Higher amounts are possible in areas that have thunderstorms as well.

With the ground still mostly frozen and saturated, it won’t be able to absorb the high rainfall amounts. This could cause flash floods, water pooling on roads and localized flooding in low-lying areas.

Rainfall warnings are expected as the system moves in Tuesday night.

It’s expected to last through Wednesday when the mild weather Toronto been experiencing will cool down drastically, dropping to -3 C overnight.

The temperatures will be back to hovering near seasonal, just above zero, later this week.

The drop in temperature will set the stage for potentially two snowy systems over the next six days. This first is expected to arrive on Friday starting as wet snow, then mixing in rain especially near the lake which will limit snowfall amounts to just a few centimetres.

The second system will be more of a wintry mess on Sunday. Get ready for many types of precipitation to fall throughout the day ranging from snow to ice pellets to freezing rain to rain.

It’s still too early to say how intense this system will be but it’s definitely one that could impact travel late in the weekend.

Extended forecast

Thursday: High: 1 C, Low: -5 C and cloudy with 30 percent chance of flurries.

Friday: High: 1 C, Low: -6 C and cloudy with 60 percent chance of snow or rain.

Saturday: High: 0 C, Low: -2 C and cloudy.

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