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fzus61 kbuf 302003
glfsl 
expires:202605010300;;799134

forecast for the saint lawrence river
including the thousand islands region
national weather service buffalo ny
403 pm edt thu apr 30 2026


slz022-024-010300-
saint lawrence river from cape vincent to saint regis
403 pm edt thu apr 30 2026

.tonight...northwest winds 5 to 10 knots becoming light and
variable. a chance of rain showers early. 
.friday...northwest winds 10 knots or less becoming west. a
chance of rain showers late. 
.friday night...southwest winds less than 10 knots. a chance of
rain showers in the evening. 
.saturday...west winds 10 knots or less. a chance of rain
showers. 
.saturday night...west winds 10 knots or less becoming southwest.
partly cloudy. 
.sunday...west winds 5 to 15 knots becoming southwest. partly to
mostly cloudy. 
.monday...southwest winds 10 to 15 knots becoming south 15 to
20 knots. showers likely. 
.tuesday...southwest winds 15 to 20 knots diminishing to 5 to
15 knots. a chance of showers. 

$$
fzus61 kbuf 302002
glflo 
expires:202605010300;;799110

open lake forecast for lake ontario
national weather service buffalo ny
402 pm edt thu apr 30 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...an elongated 29.7 inch low will gradually slide 
northeastward along the atlantic canada shoreline this evening.
this low will then retrograde northward and then northwestward 
across the canadian maritimes and quebec respectively friday and 
saturday. another 29.7 inch low will then deepen to 29.2 inches as 
it tracks from the southeastern states northeast off the atlantic 
coast saturday through sunday, while a 30.2 inch high ridges across 
the lower great lakes. a 29.1 inch low will then pinwheel 
counterclockwise about ontario, quebec, and hudson bay monday 
through tuesday night, sending an attendant cold front across the 
lake tuesday.


loz062-010300-
lake ontario open waters from the niagara river to hamlin beach-
402 pm edt thu apr 30 2026

.tonight...west winds 5 to 15 knots becoming northwest. waves
1 to 2 feet. 
.friday...west winds 5 to 10 knots. waves 1 foot or less. 
.friday night...west winds 5 to 10 knots becoming northwest.
waves 1 foot or less. 
.saturday...northwest winds 5 to 10 knots becoming west. waves
1 foot or less. 
.saturday night...west winds 5 to 10 knots becoming northwest.
waves around 1 foot. 
.sunday...west winds 10 to 15 knots becoming southwest and
increasing to 15 to 25 knots. a chance of rain showers sunday
night. waves 1 to 2 feet building to 3 to 5 feet. 
.monday...southwest winds 15 to 25 knots increasing to 30 knots.
a chance of showers. waves 3 to 6 feet building to 5 to 8 feet.
waves occasionally around 10 feet. 
.tuesday...southwest winds 15 to 25 knots becoming east and
diminishing to 10 to 15 knots. a chance of showers. waves 4 to
7 feet subsiding to 1 to 3 feet. waves occasionally around
9 feet. 

$$
fzus61 kbuf 302002
glflo 
expires:202605010300;;799111

open lake forecast for lake ontario
national weather service buffalo ny
402 pm edt thu apr 30 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...an elongated 29.7 inch low will gradually slide 
northeastward along the atlantic canada shoreline this evening.
this low will then retrograde northward and then northwestward 
across the canadian maritimes and quebec respectively friday and 
saturday. another 29.7 inch low will then deepen to 29.2 inches as 
it tracks from the southeastern states northeast off the atlantic 
coast saturday through sunday, while a 30.2 inch high ridges across 
the lower great lakes. a 29.1 inch low will then pinwheel 
counterclockwise about ontario, quebec, and hudson bay monday 
through tuesday night, sending an attendant cold front across the 
lake tuesday.


loz063>065-010300-
lake ontario open waters from hamlin beach to the saint lawrence
river-
402 pm edt thu apr 30 2026

.tonight...west winds 15 to 20 knots becoming northwest 5 to
15 knots. waves 2 to 4 feet subsiding to 1 to 3 feet. 
.friday...northwest winds 5 to 10 knots becoming west. waves
2 feet or less. 
.friday night...west winds 5 to 10 knots. waves 1 foot or less. 
.saturday...west winds 5 to 15 knots. waves 2 feet or less. 
.saturday night...west winds 5 to 10 knots becoming northwest.
waves 1 to 2 feet. 
.sunday...west winds 10 to 15 knots becoming southwest 15 to
20 knots. a chance of rain showers sunday night. waves 1 to
3 feet building to 2 to 4 feet. 
.monday...southwest winds 15 to 25 knots becoming south to
30 knots. a chance of showers. waves 2 to 4 feet building to 4 to
7 feet. waves occasionally around 9 feet. 
.tuesday...southwest winds 15 to 25 knots becoming south and
diminishing to 10 to 15 knots. a chance of showers. waves 4 to
7 feet subsiding to 1 to 3 feet. waves occasionally around
9 feet. 

$$
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