Prescott to Cornwall


Marine Forecast

Issued 10:30 AM EDT 22 August 2017

Today Tonight and Wednesday.

Strong wind warning in effect. Squall watch in effect.

Wind south 15 knots with gusts to 50 near thunderstorms. Wind becoming southwest 20 this afternoon with gusts to 50 near thunderstorms this evening. Wind diminishing to southwest 10 near midnight then becoming light Wednesday evening.

A few showers and a few thunderstorms ending near midnight. Chance of showers beginning near noon Wednesday with risk of thunderstorms.

Extended Forecast

Issued 03:00 AM EDT 22 August 2017
Thursday Wind light.
Friday Wind light.
Saturday Wind light.

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Weather Conditions

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Map of St. Lawrence - St. Lawrence River marine weather areas Mont-Louis - 45138 Lake Nipissing - 45152 North Bay Airport Beauport Deschambault L'Assomption Trois-Rivières Airport Saint-Hubert Airport Baie-Comeau Airport Cap-Rouge Pointe de l'Islet Sept-Îles Airport Cap-d'Espoir Rivière-la-Madeleine Gaspé Airport La Pocatière Mont-Joli Airport New Carlisle Pointe-au-Père Port Menier CFB Bagotville Jonquière Mistook Normandin Roberval Airport Bas Caraquet Bathurst Airport Bouctouche AAFC Charlo Miramichi Fundy Park (Alma) Grand Manan Kouchibouguac Miscou Island Greater Moncton Int'l Airport Point Lepreau Saint John Airport St. Stephen Brier Island Yarmouth Airport North Cape Île d'Orléans Île aux-Grues Lac Saint-Pierre Lac Memphremagog Sainte-Anne-de-Bellevue Saint-Anicet Île Rouge Pointe Claveau Pointe-des-Monts Pointe-Noire Île Bicquette Cap-Chat Montréal-Trudeau Int'l Airport
buoy Buoy
land station Land Station
Ice Conditions

There is no ice forecast issued for this area.


Warnings (In effect)

Strong wind warning in effect

Kingston to Cornwall

Issued 10:30 AM EDT 22 August 2017

'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

Prescott to Cornwall

Issued 09:30 AM EDT 22 August 2017 Conditions are favourable for the development of squalls with wind gusts up to 50 knots, frequent lightning, hail and poor to very poor visibility in thunderstorms heavy at times.

The severe weather threat should end by late afternoon or early evening.

Large hail can damage vessels and cause injury. Vessels without lightning protection should make their way to shore immediately. Mariners are advised to prepare for potential squalls. Vulnerable vessels are most at risk and should seek safe harbour if underway. Consider delaying or postponing travel in areas under the Squall Watch.

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


Technical Marine Synopsis

Issued 10:30 AM EDT 22 August 2017 Today Tonight and Wednesday At 10:30 a.m. EDT today deepening low 999 mb located 100 miles
north of Lake Nipissing.
By 10:30 a.m. EDT Wednesday deepening low 985 mb located east of
James Bay.

At 10:30 a.m. EDT today trough from low located on a line
northeast-southwest over northern Lake Huron.
By 10:30 a.m. EDT Wednesday trough located on a line
northeast-southwest over the Eastern Seaboard.

St. Lawrence - St. Lawrence River Area

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