Southern Ontario: Fall Weather Hazards Outlook for Thursday, November 18, 2021

Forecast Discussion

The lake effect machine will kick back into gear to end off the week for Thursday and affect areas mainly to the east of Georgian Bay. We will see the development of lake effect snow beginning Thursday afternoon around the Parry Sound and Muskoka region. Although they won’t really get organized until after the dinner hour when some localized strong squalls may develop and continue into the overnight hours. A few hours of heavy snow is possible through the Hwy 400 and Hwy 11 corridor between Parry Sound to Honey Harbor and Huntsville to Gravenhurst with poor travel conditions during the evening.

Localized totals of up to 15cm can’t be ruled out should the squall lock into a particular area for a few hours. A more general estimate would be around 5-10cm, but it’s hard to predict as these squalls are so localized. There will also be some less organized activity off Lake Huron that will bring around 5cm at most with locally up to 10cm for the Hanover and Meaford area.

The wind direction will shift bringing the weakening squall southward into parts of Simcoe County and Kincardine/Listowel area early Friday morning. They will fully dissipate by late Friday morning so accumulation should be limited on Friday.