Blast of Arctic Air to Bring the Coldest Temperatures of the Season Across Southern Ontario on Friday Morning With Wind Chills Near -15°C

It’s hard to believe that less than a week ago we were talking about late summer-like weather with temperatures above 20°C and the threat of tornadoes. Now the story this Friday will be temperatures well below the freezing mark and in some cases, reaching into the negative double digits! This will no doubt be the coldest temperatures that Southern Ontario has seen this season.

Cold air from Northern Ontario is expected to flow into our region overnight Thursday. When you wake up early Friday morning, the thermometer will read between -5°C and -10°C through much of Central and Northeastern Ontario. When you factor in the wind chill it’ll feel into the double digits reaching as cold as -15°C. Further south, the temperature will be slightly warmer with temperatures between 0°C and -5°C with a wind chill between -5°C and -10°C including much of Eastern and Southwestern Ontario away from the lakes. The rest of Southern Ontario around Lake Ontario and Erie can expect temperatures flirting with the freezing mark but should stay slightly above it.

As for Halloween, the morning will start on a chilly note similar to Friday but temperatures should warm up to above the freezing mark throughout the day on Saturday in time for Trick or Treating. We’ll have more details in our special Halloween outlook that will be released either Thursday evening or Friday afternoon. Stay tuned!

We’re also closely monitoring the potential for our first substantial lake effect snow event with snow squalls developing Sunday and lasting into Monday. At this moment, the area in the bullseye for the heaviest snowfall accumulation is around Lake Huron and south of Georgian Bay, but that is subject to change. Some localized regions could see as much as 10-20cm of snowfall accumulation by the middle of next week! More details soon.