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ON- Lake Ontario

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fzus61 kbuf 220205
glfsl 
expires:202604220900;;774222

forecast for the saint lawrence river
including the thousand islands region
national weather service buffalo ny
1005 pm edt tue apr 21 2026


slz022-024-220900-
saint lawrence river from cape vincent to saint regis
1005 pm edt tue apr 21 2026

.overnight...southeast winds 5 to 10 knots. mostly cloudy. 
.wednesday...southeast winds less than 10 knots. mostly cloudy
through early afternoon, then becoming partly sunny. 
.wednesday night...light and variable winds. partly cloudy. 
.thursday...northwest winds 10 knots or less. mostly sunny. 
.thursday night...northwest winds 10 knots or less becoming
north. partly cloudy. 
.friday...north winds 10 knots or less becoming east. mainly
clear. 
.saturday...northeast winds 5 to 10 knots becoming light and
variable. partly cloudy. 
.sunday...light and variable winds. partly cloudy. 

$$
fzus61 kbuf 220204
glflo 
expires:202604220900;;774150

open lake forecast for lake ontario
national weather service buffalo ny
1004 pm edt tue apr 21 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 weak 29.4 inch low will cross the area tonight, and in 
the process drag an attendant cold front across the lake. a 30.1 
inch high will then build across the great lakes region wednesday 
and thursday. a warm front will approach the lake by friday. a 29.7 
inch low will move southwest of the lake on saturday, followed by a 
30.2 inch high building across the lake saturday night and sunday.


loz062-220900-
lake ontario open waters from the niagara river to hamlin beach-
1004 pm edt tue apr 21 2026

.overnight...southeast winds 10 knots or less becoming
south. waves 1 to 2 feet. 
.wednesday...northeast winds less than 10 knots becoming
southwest. waves 1 foot or less. 
.wednesday night...west winds 10 knots or less becoming
northwest. waves 1 foot or less. 
.thursday...northwest winds less than 10 knots becoming
southwest. waves 1 foot or less. 
.thursday night...southwest winds 10 knots or less becoming
northeast 10 to 15 knots. waves 2 feet or less. 
.friday...east winds 10 to 15 knots increasing to 15 to 20 knots.
a chance of rain showers friday night. waves 1 to 3 feet building
to 3 to 6 feet. 
.saturday...east winds 15 to 25 knots diminishing to 10 to
15 knots. a chance of showers. waves 4 to 7 feet subsiding to
3 to 6 feet. waves occasionally around 9 feet. 
.sunday...east winds 5 to 15 knots. waves 1 to 3 feet. 

$$
fzus61 kbuf 220204
glflo 
expires:202604220900;;774151

open lake forecast for lake ontario
national weather service buffalo ny
1004 pm edt tue apr 21 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 weak 29.4 inch low will cross the area tonight, and in 
the process drag an attendant cold front across the lake. a 30.1 
inch high will then build across the great lakes region wednesday 
and thursday. a warm front will approach the lake by friday. a 29.7 
inch low will move southwest of the lake on saturday, followed by a 
30.2 inch high building across the lake saturday night and sunday.


loz063>065-220900-
lake ontario open waters from hamlin beach to the saint lawrence
river-
1004 pm edt tue apr 21 2026

.overnight...southeast winds 15 to 20 knots diminishing to
10 to 15 knots. waves 1 to 3 feet. 
.wednesday...southeast winds 5 to 15 knots becoming northwest
less than 10 knots. waves 2 feet or less. 
.wednesday night...west winds 10 knots or less becoming
northwest. waves 1 foot or less. 
.thursday...north winds 5 to 10 knots becoming west. waves 1 foot
or less. 
.thursday night...west winds 10 knots or less becoming northeast.
waves 1 foot or less. 
.friday...northeast winds 5 to 15 knots becoming east 15 to
20 knots. a chance of rain showers friday night. waves 2 feet or
less building to 2 to 4 feet. 
.saturday...east winds 15 to 20 knots becoming southeast 10 to
15 knots. a chance of rain showers. waves 3 to 5 feet subsiding
to 1 to 3 feet. 
.sunday...east winds 5 to 15 knots. waves 1 to 3 feet subsiding
to 1 foot or less. 

$$
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