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ON- Lake Ontario

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fzus61 kbuf 052010
glfsl 
expires:202604060300;;889110

forecast for the saint lawrence river
including the thousand islands region
national weather service buffalo ny
410 pm edt sun apr 5 2026


slz022-024-060300-
saint lawrence river from cape vincent to saint regis
410 pm edt sun apr 5 2026

...small craft advisory in effect until 10 pm edt this evening...

.tonight...west winds 15 to 20 knots diminishing to 10 to
15 knots. a chance of rain showers early. a chance of snow
showers after midnight. 
.monday...west winds 5 to 15 knots. a chance of snow showers
late. 
.monday night...northwest winds 10 knots or less becoming north
10 to 15 knots. a chance of snow showers in the evening, then
snow showers likely overnight. 
.tuesday...north winds 5 to 15 knots becoming northwest. snow
showers likely in the morning. 
.tuesday night...west winds 10 knots or less becoming southwest.
mainly clear. 
.wednesday...southwest winds 5 to 15 knots becoming south. mainly
clear, then becoming partly cloudy. 
.thursday...south winds 10 to 15 knots becoming southwest. a
chance of rain showers thursday night. 
.friday...southwest winds 10 knots or less becoming northwest. a
chance of rain showers. 

$$
fzus61 kbuf 052009
glflo 
expires:202604060300;;888748

open lake forecast for lake ontario
national weather service buffalo ny
409 pm edt sun apr 5 2026

for waters beyond five nautical miles of shore on lake ontario

waves are the significant wave height - the average of the highest
1/3 of the wave spectrum. occasional wave height is the average of
the highest 1/10 of the wave spectrum.

.synopsis... a 29.1 inch low over quebec will push its trailing 
secondary and tertiary cold fronts across the lake tonight and 
monday. a 30.5 inch high will build across the great lakes tuesday 
and tuesday night, before sliding east and off the new england coast 
wednesday. a 29.6 inch surface low will then track northeast across 
ontario and quebec, and will eventually slide its trailing cold 
front across the lake thursday night and friday.


loz062-060300-
lake ontario open waters from the niagara river to hamlin beach-
409 pm edt sun apr 5 2026

.tonight...west winds 15 to 25 knots. waves 5 to 8 feet. waves
occasionally around 10 feet. 
.monday...west winds 15 to 20 knots diminishing to 5 to 15 knots.
a chance of rain and snow showers late. waves 3 to 5 feet
subsiding to 1 to 3 feet. 
.monday night...northwest winds 5 to 15 knots increasing to 15 to
25 knots. snow showers with rain showers likely in the evening,
then snow showers overnight. waves 1 to 2 feet building to 3 to
6 feet. 
.tuesday...northwest winds 15 to 25 knots. snow showers likely in
the morning. waves 3 to 6 feet subsiding to 2 to 4 feet. 
.tuesday night...northwest winds 15 to 20 knots becoming
southwest 5 to 15 knots. waves 2 to 4 feet subsiding to 1 to
3 feet. 
.wednesday...south winds 5 to 15 knots increasing to 15 to
20 knots. waves 2 feet or less building to 2 to 4 feet. 
.thursday...south winds 15 to 25 knots becoming southwest. a
chance of showers. waves 3 to 5 feet subsiding to 2 to 4 feet. 
.friday...southwest winds 10 to 15 knots becoming northwest. a
chance of showers. waves 1 to 3 feet. 

$$
fzus61 kbuf 052009
glflo 
expires:202604060300;;888749

open lake forecast for lake ontario
national weather service buffalo ny
409 pm edt sun apr 5 2026

for waters beyond five nautical miles of shore on lake ontario

waves are the significant wave height - the average of the highest
1/3 of the wave spectrum. occasional wave height is the average of
the highest 1/10 of the wave spectrum.

.synopsis... a 29.1 inch low over quebec will push its trailing 
secondary and tertiary cold fronts across the lake tonight and 
monday. a 30.5 inch high will build across the great lakes tuesday 
and tuesday night, before sliding east and off the new england coast 
wednesday. a 29.6 inch surface low will then track northeast across 
ontario and quebec, and will eventually slide its trailing cold 
front across the lake thursday night and friday.


loz063>065-060300-
lake ontario open waters from hamlin beach to the saint lawrence
river-
409 pm edt sun apr 5 2026

.tonight...west winds 15 to 25 knots. a chance of snow showers
after midnight. waves 5 to 9 feet. waves occasionally around
11 feet. 
.monday...west winds 15 to 20 knots diminishing to 10 to
15 knots. a chance of snow showers in the morning. waves 4 to
7 feet subsiding to 2 to 4 feet. waves occasionally around
9 feet. 
.monday night...west winds 10 to 15 knots becoming northwest and
increasing to 15 to 25 knots. snow showers. waves 1 to 3 feet
building to 3 to 6 feet. 
.tuesday...northwest winds 15 to 25 knots becoming west. snow
showers likely in the morning, then a chance of snow showers in
the afternoon. waves 4 to 7 feet subsiding to 3 to 6 feet. waves
occasionally around 9 feet. 
.tuesday night...west winds 15 to 20 knots diminishing to 5 to
15 knots. waves 3 to 5 feet subsiding to 1 to 3 feet. 
.wednesday...south winds 5 to 10 knots increasing to 30 knots.
waves 1 to 3 feet building to 3 to 6 feet. 
.thursday...south winds to 30 knots. a chance of rain showers
thursday night. waves 4 to 7 feet subsiding to 3 to 6 feet. waves
occasionally around 9 feet. 
.friday...south winds 15 to 20 knots becoming northwest 5 to
15 knots. a chance of rain showers. waves 3 to 6 feet subsiding
to 1 to 3 feet. 

$$
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