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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 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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Ice Conditions

There is no ice forecast issued for this area.

Warnings

Warnings (In effect)

Strong wind warning in effect

Cornwall to Montréal

Issued 09:03 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 Erie and Lake Ontario Area

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