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Cornwall to Montréal

Forecast

Marine Forecast

Issued 03:00 AM EST 17 December 2025

Today Tonight and Thursday.

Wind southwest 10 to 15 knots increasing to southwest 15 to 25 this morning then becoming west 15 this evening. Wind diminishing to light near midnight then becoming southerly 15 Thursday afternoon.

Showers or scattered flurries this afternoon and this evening.

High today plus 3. Low tonight minus 5. High Thursday plus 3.

Extended Forecast

Issued 06:00 PM EST 16 December 2025
Thursday Wind light increasing to south 15 to 25 knots in the afternoon.
Friday Wind south 15 to 25 knots increasing to southwest 25 to 35.
Saturday Wind west 15 to 25 knots diminishing to light late in the day.

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Weather Conditions

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Map of Great Lakes - Lake Erie and Lake Ontario marine weather areas Harrow AAFC Burlington Lift Bridge Oshawa Executive Airport Point Pelee Peterborough Municipal Airport Point Petre Hamilton Munro Int'l Airport Erieau Cobourg Toronto City Centre Airport Port Colborne CFB Trenton South Lake Huron - 45149 Windsor Airport Great Duck Island Gore Bay-Manitoulin Airport North Bay Airport Greater Sudbury Airport Killarney Sault Ste. Marie Airport Ajax - 45159 North Channel - 45154 Lake Nipissing - 45152 Lake Simcoe - 45151 Welland-Pelham Lake St Clair - 45147 South Georgian Bay - 45143 Port Colborne - 45142 Grimsby - 45139 Georgian Bay - 45137 Prince Edward Point - 45135 Port Stanley - 45132 Vineland Station Brockville Grenadier Island Kingston Airport Collingwood Lagoon City Muskoka Airport Parry Sound Harbour Lake Simcoe Regional Airport Wiarton Airport Cove Island Goderich Sarnia Chris Hadfield Airport Western Islands Tobermory Long Point Port Weller St. Catharines / Niagara District Airport Southeast Shoal
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land station Land Station
Ice Conditions

There is no ice forecast issued for this area.

Warnings

No watches or warnings in effect.

Synopsis

Technical Marine Synopsis

Issued 3:00 AM EST 17 December 2025 Today Tonight and Thursday At 3:00 a.m. EST today departing ridge located on a line north-south
over Newfoundland.

At 3:00 a.m. EST today trough located on a line northeast-southwest
over northwestern Québec city.
By 3:00 a.m. EST Thursday departing trough located on a line
north-south over Newfoundland.

At 3:00 p.m. EST today ridge located on a line north-south over
the Great Lakes.
By 7:00 p.m. EST Thursday ridge located on a line
northwest-southeast over the Gulf of St. Lawrence.

Great Lakes - Lake Erie and Lake Ontario Area

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