Great Lakes Forecast
Issued by NWS

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669
FZUS61 KBUF 131402
GLFLO

Open Lake Forecast for Lake Ontario
National Weather Service Buffalo NY
1002 AM EDT Sun Jul 13 2025

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 near James Bay will lift north across
Hudson Bay and into northern Quebec today... while slowly dragging
its trailing cold front across the lake tonight. A 30.1 inch high
will slowly drift from the Upper Midwest to New England Monday
through Wednesday...then a 29.7 inch low will track northeastward
across the Great Lakes and into Quebec Wednesday night and Thursday.

LOZ062-132100-
Lake Ontario open waters from the Niagara River to Hamlin Beach-
1002 AM EDT Sun Jul 13 2025

.REST OF TODAY...Southwest winds 5 to 10 knots. A chance of
showers and thunderstorms. Waves 1 to 2 feet.
.TONIGHT...Southwest winds 10 knots or less becoming northwest. A
chance of showers and thunderstorms early, then a chance of
showers late in the evening. Waves 2 feet or less.
.MONDAY...Light and variable winds becoming south 5 to 10 knots.
Waves 1 foot or less.
.MONDAY NIGHT...South winds 5 to 10 knots becoming west. Waves
1 foot or less.
.TUESDAY...West winds 10 knots or less becoming south. Waves
1 foot or less.
.WEDNESDAY...Southwest winds 10 knots or less. A chance of
showers. Waves 2 feet or less.
.THURSDAY...Southwest winds 10 to 15 knots becoming northwest. A
chance of showers and thunderstorms. Waves 1 to 2 feet.

Winds and waves higher in and near thunderstorms.

$$

LOZ063>065-132100-
Lake Ontario open waters from Hamlin Beach to the Saint Lawrence
River-
1002 AM EDT Sun Jul 13 2025

.REST OF TODAY...Southwest winds 5 to 15 knots becoming south. A
chance of showers and thunderstorms late this morning, then
showers with thunderstorms likely this afternoon. Waves 1 to
3 feet.
.TONIGHT...South winds 10 knots or less becoming southwest.
Showers likely with a chance of thunderstorms early, then a
chance of showers and thunderstorms. Waves 2 feet or less.
.MONDAY...West winds 10 knots or less becoming southwest. Waves
1 foot or less.
.MONDAY NIGHT...Southwest winds 10 knots or less. Waves 1 foot or
less.
.TUESDAY...Southwest winds 10 knots or less becoming south. Waves
1 foot or less.
.WEDNESDAY...South winds 5 to 10 knots. A chance of showers
during the day, then a chance of showers and thunderstorms
Wednesday night. Waves 2 feet or less.
.THURSDAY...Southwest winds 5 to 15 knots becoming northwest.
Showers likely with a chance of thunderstorms. Waves 1 to 2 feet.

Winds and waves higher in and near thunderstorms.

$$

LOZ061-132100-
MAFOR 1315/
ONTARIO WEST 1/2 11600 13500 12700 11600 11700. A chance of
showers and thunderstorms this afternoon and evening. Waves 2
feet or less.

ONTARIO EAST 1/2 11510 11506 13400 11500 12600. A chance of
thunderstorms this afternoon and evening. Waves 2 feet or less.

$$