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fzus61 kbuf 220203
glflo 
expires:202607220900;;382465

open lake forecast for lake ontario
national weather service buffalo ny
1002 pm edt tue jul 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 29.3 inch low will be near james bay with multiple frontal 
boundaries crossing the lake through tonight. a secondary cold 
front will cross the lake wednesday, with a 30.2 inch high 
building across the lower great lakes region wednesday night 
through friday. the high will move off the east coast saturday.


loz062-220900-
lake ontario open waters from the niagara river to hamlin beach-
1002 pm edt tue jul 21 2026

.rest of tonight...west winds 15 to 20 knots. a chance of showers
and thunderstorms late this evening, then a chance of showers
after midnight. some thunderstorms may produce gusty winds late
this evening. waves 3 to 6 feet. 
.wednesday...west winds 15 to 25 knots. waves 3 to 6 feet. 
.wednesday night...northwest winds 15 to 20 knots becoming west
and diminishing to around 10 knots. waves 3 to 5 feet subsiding
to 1 to 3 feet. 
.thursday...west winds 5 to 10 knots becoming southwest. waves
2 feet or less. 
.thursday night...southwest winds 10 knots or less. waves 1 foot
or less. 
.friday...south winds 10 knots or less becoming southeast. waves
1 foot or less. 
.saturday...south winds 10 knots or less becoming southwest.
waves 1 foot or less. 
.sunday...southwest winds 5 to 10 knots becoming west. a chance
of showers. waves 2 feet or less. 

winds and waves higher in and near thunderstorms.

$$
fzus61 kbuf 220203
glflo 
expires:202607220900;;382466

open lake forecast for lake ontario
national weather service buffalo ny
1002 pm edt tue jul 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 29.3 inch low will be near james bay with multiple frontal 
boundaries crossing the lake through tonight. a secondary cold 
front will cross the lake wednesday, with a 30.2 inch high 
building across the lower great lakes region wednesday night 
through friday. the high will move off the east coast saturday.


loz063>065-220900-
lake ontario open waters from hamlin beach to the saint lawrence
river-
1002 pm edt tue jul 21 2026

.rest of tonight...west winds 15 to 25 knots. showers with a
chance of thunderstorms late this evening, then a chance of
showers after midnight. some thunderstorms may produce gusty
winds late this evening. waves 2 to 4 feet building to 4 to
7 feet. waves occasionally around 9 feet. 
.wednesday...west winds 20 to 25 knots. waves 5 to 8 feet. waves
occasionally around 10 feet. 
.wednesday night...west winds 15 to 25 knots diminishing to 5 to
15 knots. waves 5 to 8 feet subsiding to 1 to 3 feet. waves
occasionally around 10 feet. 
.thursday...west winds 5 to 15 knots. waves 1 to 2 feet. 
.thursday night...southwest winds 5 to 15 knots. waves 2 feet or
less. 
.friday...south winds 10 knots or less becoming southeast. waves
1 foot or less. 
.saturday...south winds 5 to 15 knots. waves 2 feet or less. 
.sunday...southwest winds 5 to 15 knots. a chance of showers
during the day, then showers likely sunday night. waves 2 feet or
less. 

winds and waves higher in and near thunderstorms.

$$
fzus61 kbuf 220203
glfsl 
expires:202607220900;;382476

forecast for the saint lawrence river
including the thousand islands region
national weather service buffalo ny
1003 pm edt tue jul 21 2026


slz022-024-220900-
saint lawrence river from cape vincent to saint regis
1003 pm edt tue jul 21 2026

.rest of tonight...south winds 5 to 15 knots becoming southwest.
showers with a chance of thunderstorms, then a chance of showers
late. some thunderstorms may produce gusty winds late this
evening. 
.wednesday...west winds 10 to 15 knots. a chance of showers. 
.wednesday night...west winds 5 to 15 knots becoming southwest
less than 10 knots. a chance of showers in the evening. 
.thursday...southwest winds 10 knots or less becoming west.
sunny.
.thursday night...southwest winds 10 knots or less. mainly clear.
.friday...southwest winds less than 10 knots. mainly clear. 
.saturday...south winds 10 knots or less. mainly clear, then
becoming partly cloudy. 
.sunday...south winds 10 knots or less becoming southwest. a
chance of showers during the day, then showers likely sunday
night. 

winds and waves higher in and near thunderstorms.

$$
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