Eastern Lake Ontario
Forecast
Marine Forecast
Issued 06:30 PM EDT 21 June 2025
Tonight and Sunday.
Strong wind warning in effect.
Wind southeast 10 knots increasing to south 15 this evening and to southwest 20 late overnight. Wind diminishing to southwest 15 near noon Sunday.
Scattered showers this evening. Scattered showers overnight and Sunday morning with a risk of thunderstorms.
Waves
Issued 06:30 PM EDT 21 June 2025
Tonight and Sunday.
Waves 0.5 metres or less building to 0.5 to 1 near midnight and
to 1 to 1.5 early Sunday morning. Waves subsiding to 0.5 to 1 Sunday
afternoon.
Extended Forecast
Issued 06:30 PM EDT 21 June 2025
Monday
Wind southwest 15 knots.
Tuesday
Wind west 15 knots diminishing to light late
in the day.
Wednesday
Wind light.
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Weather Conditions
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Ice Conditions
*Ice Forecast and Warnings also apply to U.S. waters
Ice Forecasts
Issued 12:00 PM EDT 16 May 2025 Forecasts have ended for the season.Warnings
Warnings (In effect)
Strong wind warning in effect
Eastern Lake Ontario
Issued 6:30 PM EDT 21 June 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
Eastern Lake Ontario
Issued 00:46 AM EDT 22 June 2025 Conditions are favourable for the development of squalls with wind gusts up to 50 knots, frequent lightning and hail.An area of thunderstorms over central Ontario will move southeastward through early this morning.
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 6:30 PM EDT 21 June 2025 Tonight and Sunday At 6:30 p.m. EDT tonight departing low 1000 mb located nearJames Bay.
At 6:30 p.m. EDT tonight low 996 mb located over South Dakota.
By 6:30 p.m. EDT Sunday low 996 mb located over western North
Dakota.
Great Lakes - Lake Erie and Lake Ontario Area
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