A frosty Saturday night ahead across much of Southern Ontario. Pleasant conditions Sunday, give way to a pair of clipper systems to start the work week. 

It will be a cool and frosty Sunday morning across Southern Ontario. Sunny conditions, and light southwesterly winds, will allow temperatures to rebound in the afternoon.  The first of two clipper systems brings rain showers (beginning) Monday morning. Dreary and cool conditions continue through the afternoon. 

First Shot of Lake Effect Snow?

A clipper system will track through the Great Lakes late Tuesday through Wednesday. The passage of the low will be followed by a reinforcing shot of cold and dry air. Lake effect rainfall may bring graupel or hail to some locales in Central Ontario (Tuesday evening into Wednesday morning). Owing to, instability, and seasonably cold air building aloft.

Lake effect rainfall bands will transition to wet snowfall Wednesday night, Southeast of Lake Huron, and Georgian Bay.

Seasonably cool air 1.5km above the surface, will support lake effect snow. Abundant dry air, warm ground temperatures, and a building area of high pressure, should mitigate any risk of significant accumulation. We will monitor the risk over the coming days.