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Cornwall to Montréal

Forecast

Marine Forecast

Issued 05:47 AM EDT 17 July 2025

Today Tonight and Friday.

Strong wind warning in effect.

Wind light increasing to southwest 20 to 30 knots near noon with gusts to 50 near thunderstorms. Wind becoming northwest 15 to 25 early this evening then becoming westerly 15 Friday morning.

Showers ending this evening with a risk of thunderstorms. Visibility 1 mile or less in showers.

Extended Forecast

Issued 06:00 AM EDT 17 July 2025
Saturday Wind southwest 10 to 15 knots increasing to southwest 15 to 20 in the morning.
Sunday Wind southwest 10 to 15 knots veering to northwest 10 to 15.
Monday Wind northwest 10 to 15 knots.

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Weather Conditions

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

There is no ice forecast issued for this area.

Warnings

Warnings (In effect)

Strong wind warning in effect

Cornwall to Montréal

Issued 05:47 AM EDT 17 July 2025

'Strong' winds of 20 to 33 knots are occurring or expected to occur in this marine area. Please refer to the latest marine forecasts for further details and continue to monitor the situation through Canadian Coast Guard radio or Weatheradio stations.

Watches (In effect)

Squall watch in effect

Cornwall to Montréal

Issued 05:53 AM EDT 17 July 2025 This afternoon and this evening, conditions will be favourable for the development of squalls with wind gusts up to 50 knots and frequent lightning.

Please continue to monitor alerts and forecasts issued by Environment Canada. For more information monitor Canadian Coast Guard radio or Weatheradio stations.

Synopsis

Technical Marine Synopsis

Issued 3:00 AM EDT 17 July 2025 Today Tonight and Friday At 3:00 a.m. EDT today low 1004 mb located over Lake Huron.
By 8:00 p.m. EDT Friday low 988 mb located over Labrador.

At 3:00 a.m. EDT today high located south of Manitoba.
By 8:00 p.m. EDT Friday high located over Lake Ontario.

Great Lakes - Lake Huron Area

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