Cornwall to Montréal
Forecast
Marine Forecast
Issued 03:00 PM EDT 21 June 2025
Tonight and Sunday.
Wind light increasing to southeast 10 to 15 knots early this evening and to westerly 15 to 20 near midnight. Wind diminishing to west 10 to 15 Sunday afternoon and to light Sunday evening.
Showers overnight and Sunday morning with a risk of thunderstorms. Scattered showers Sunday evening. Visibility as low as 1 mile in showers.
Extended Forecast
Issued 06:00 PM EDT 21 June 2025
Monday
Wind light increasing to southwest 15 to 25
knots in the afternoon.
Tuesday
Wind southwest 10 to 20 knots.
Wednesday
Wind northwest 15 knots veering to northeast
10 to 15 late in the day.
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Weather Conditions
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Ice Conditions
There is no ice forecast issued for this area.
Warnings
Watches (In effect)
Squall watch in effect
Cornwall to Montréal
Issued 4:40 PM EDT 21 June 2025 Overnight tonight, conditions are favourable for the development of squalls with wind gusts up to 50 knots, frequent lightning and hail.Mariners are advised to prepare for potential squalls. Vulnerable vessels are most at risk and should seek safe harbour if underway.
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 PM EDT 21 June 2025 Tonight and Sunday At 3:00 p.m. EDT today departing low 995 mb located off Labrador.At 3:00 p.m. EDT today ridge located from Hudson Bay to Maine.
By 8:00 p.m. EDT Sunday weakening ridge located on a line
north-south over Newfoundland.
At 8:00 p.m. EDT tonight low located south of James Bay.
By 8:00 p.m. EDT Sunday weakening low located over New Brunswick.
Great Lakes - Lake Huron Area
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