We are watching the risk for some significant snow squalls across Southwestern Ontario with blizzard-like conditions possible.
Areas in the red and marked with a '5' can expect snowfall totals between 20 and 40cm of snow with local amounts near or over 50cm. This extends from Lake Huron around Kincardine, Amberley and Point Albert extending inland along Highway 9 and Highway 86 to impact Wingham, Listowel, Minto, and Mildmay. In this region, the strongest snow squall of the event is expected to set up with the highest snowfall rates of 6-8cm/h. Snowfall totals in the hardest part of the snow squall may reach 50cm or even slightly higher.
Areas in the orange and marked with a '4' can expect snowfall totals between 15 and 25cm with local pockets of 25-35cm. This includes a large portion of Southwestern Ontario to the east of Lake Huron including most of Central Grey and Bruce Counties and much of Perth and Southern Huron Counties. This includes Southampton through to Chatsworth, Hanover, Monkton, Mitchell, Clinton, and Goderich. Snowfall totals across most of the region will peak near 15cm although areas that see stronger bands at times could see those totals increased to 25cm. Areas that see extended periods of stronger bands could see amounts between 25 and 35cm of snow. This is most likely into Central Bruce County between Chesley and Underwood. There is some uncertainty whether a moderate to heavy band will develop from Goderich through to Exeter into Northern Middlesex County. If this band occurs, amounts near 25cm will be likely between Goderich and Clinton. Areas across Simcoe County from the Blue Mountains through to Collingwood, Wasaga Beach, Elmsville and Angus can expect snowfall totals near 20cm. Pockets of 15cm are possible closer to Meaford with pockets closer to 20-35cm in the Collingwood-Wasaga-Stayner regions. Barrie is on the border of this region and will likely pass with just 15-20cm.
Areas in the yellow and marked with a '3' can expect snowfall totals between 10 and 20cm with pockets towards 25cm. First, areas from Bayfield through to Exeter, Lucan, Thorndale, and Stratford can expect snowfall totals in the 15-20cm range. Lesser amounts are likely towards Birr and Grand Bend where amounts near 10cm are likely. The hardest hit will be from Exeter and Granton north through to Stratford and Bayfield where up to 20cm is likely. If a strong band develops as mentioned in the 'orange' region, local amounts in this region could reach up to 25cm. Inland from Lake Huron, areas from Elmira through to Arthur, Shelburne, Bradford, Keswick, Sutton, Georgina Island, Orillia, and Port Severn can expect snowfall totals between 10 and 15cm. This also includes Wiarton and Cape Croker. Areas such as Mount Forest, Markdale, Owen Sound, Midland, Barrie, and Singhampton can expect snowfall totals between 15 and 20cm. Areas closest towards Barrie, Markdale, and Mount Forest could locally exceed 25cm.
Areas in the green and marked with a '2' can expect snowfall totals between 5 and 10cm. This includes Grand Bend through to London, Woodstock, and Kitchener. These areas can expect 5 to 10cm of snow with pockets of 15cm mixed in. This also includes Orangeville, Caledon, Elba, Grand Valley, Newmarket, and Beaverton. Areas towards Tavistock, St. Jacobs, and Grand Valley could locally see between 15 and 20cm of snow, although a general 5 to 10cm is currently expected for a majority of this region. Areas towards Brantford, Erin, Uxbridge, Lindsay, Kawartha Lakes, Gravenhurst, Moose Deer Point, Lion's Head and Tobermory can expect snowfall totals near 5cm. Up to 10cm is possible for areas including Lion's Head and Pefferlaw.
Areas in the blue and marked with a '1' can expect snowfall totals under 5cm of snow. This includes the remaining portion of Southern Ontario including the GTA as isolated snow squall bands may extend briefly in and out of the GTA as well as the morning arctic front which will bring a general 1-3cm across the region.
Conditional Notes: A few unknown conditions which will not be known until the event is taking it, is how long the band will become stationary for which will have an impact on the snowfall totals, as well as that, a few kilometers change in the location will slide this region north or south as well. Do keep these in mind as you look through the map.
Widespread winds of 50-60km/h inland from the lake and winds of 60-80km/h on the shores of Lake Huron will create for whiteout conditions and hazardous travel. At times, blizzard-like conditions will be present. Road closures are expected along the shores of Lake Huron and will be possible across portions of Huron-Perth, Grey-Bruce, and into Simcoe County.
We will be closely watching these squalls and reporting of school closures and road closures on our website, Twitter, and Facebook. These can all be found on our website here: https://www.weatherwatcher.space/oww
Our snow day forecast has also been posted for Southern Ontario: https://www.weatherwatcher.space/weather-day/Southern-Ontario
Tomorrow is expected to be a hazardous day across Southwestern Ontario. Avoid unnecessary travel.