fzus61 kbuf 170802
glflo 
expires:202608171500;;336480

open lake forecast for lake ontario
national weather service buffalo ny
402 am edt mon aug 17 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 cold front sweeps eastward across lake ontario through this late 
morning. behind the front, a trough averaging 29.8 inches lingers 
over lake ontario today. a high pressure ridge averaging 30.0 inches 
builds from the upper midwest tonight and traverses lake ontario on 
tuesday. the ridge will begin to exit eastward tuesday night before 
a cold front sweeps southeastward across the lake wednesday. behind 
the cold front, a 30.1 inch high will build from the upper midwest 
through this friday.


loz062-171500-
lake ontario open waters from the niagara river to hamlin beach-
402 am edt mon aug 17 2026

.today...west winds 5 to 10 knots. waves 2 feet or less. 
.tonight...northwest winds 5 to 10 knots becoming north. waves
2 feet or less. 
.tuesday...northwest winds 10 knots or less becoming southwest.
waves 1 foot or less. 
.tuesday night...southwest winds 10 to 15 knots. showers likely
overnight. waves 1 to 3 feet. 
.wednesday...west winds 5 to 15 knots becoming northwest. showers
likely during the day, then a chance of showers wednesday night.
waves 1 to 2 feet. 
.thursday...northwest winds 10 knots or less becoming north.
waves 1 foot or less. 
.friday...northeast winds 10 knots or less becoming south. waves
1 foot or less. 

$$

fzus61 kbuf 170802
glflo 
expires:202608171500;;336481

open lake forecast for lake ontario
national weather service buffalo ny
402 am edt mon aug 17 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 cold front sweeps eastward across lake ontario through this late 
morning. behind the front, a trough averaging 29.8 inches lingers 
over lake ontario today. a high pressure ridge averaging 30.0 inches 
builds from the upper midwest tonight and traverses lake ontario on 
tuesday. the ridge will begin to exit eastward tuesday night before 
a cold front sweeps southeastward across the lake wednesday. behind 
the cold front, a 30.1 inch high will build from the upper midwest 
through this friday.


loz063>065-171500-
lake ontario open waters from hamlin beach to the saint lawrence
river-
402 am edt mon aug 17 2026

.today...southwest winds 5 to 15 knots becoming northwest. a
chance of showers and thunderstorms early, then a chance of
showers. waves 2 feet or less. 
.tonight...northwest winds 10 knots or less becoming north. waves
2 feet or less. 
.tuesday...north winds 10 knots or less becoming west. waves
1 foot or less. 
.tuesday night...west winds 5 to 15 knots becoming southwest. a
chance of showers overnight. waves 2 feet or less. 
.wednesday...southwest winds 5 to 15 knots becoming northwest.
showers likely during the day, then a chance of showers wednesday
night. waves 1 to 3 feet. 
.thursday...northwest winds 10 knots or less. waves 1 foot or
less. 
.friday...southwest winds 10 knots or less becoming southeast.
waves 1 foot or less. 

winds and waves higher in and near thunderstorms.

$$

fzus61 kcle 170744
glfle 
expires:202608171415;;336000

open lake forecast for lake erie
national weather service cleveland oh
344 am edt mon aug 17 2026

for waters beyond five nautical miles of shore on lake erie

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...
high pressure 30.00 inches will build from the north today and 
move south of the lake on tuesday. a cold front will cross the 
lake on wednesday. high pressure 30.20 inches will build back over
the lake on thursday and friday.


lez165>167-171415-
vermilion to avon point oh beyond 5 nm off shoreline to us-
canadian border-
avon point to willowick oh beyond 5 nm off shoreline to us-
canadian border-willowick to geneva-on-the-
lake oh beyond 5nm off shoreline to us-canadian border-
344 am edt mon aug 17 2026

.today...north winds 15 to 20 knots becoming northwest 5 to
15 knots. waves 2 to 4 feet subsiding to 1 to 2 feet. 
.tonight...north winds 5 to 15 knots. waves 2 feet or less. 
.tuesday...north winds 10 knots or less becoming west. waves
2 feet or less. 
.tuesday night...southwest winds 5 to 15 knots. showers likely
overnight. waves 1 to 3 feet. 
.wednesday...west winds 5 to 15 knots becoming northeast. a
chance of showers. waves 1 to 3 feet. 
.thursday...northeast winds 5 to 10 knots becoming east. waves
around 1 foot. 
.friday...east winds 10 knots or less becoming south. waves
1 foot or less. 

$$

fzus61 kcle 170744
glfle 
expires:202608171415;;336001

open lake forecast for lake erie
national weather service cleveland oh
344 am edt mon aug 17 2026

for waters beyond five nautical miles of shore on lake erie

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...
high pressure 30.00 inches will build from the north today and 
move south of the lake on tuesday. a cold front will cross the 
lake on wednesday. high pressure 30.20 inches will build back over
the lake on thursday and friday.


lez061-168-169-171415-
ripley to buffalo ny extending from 5nm off shoreline to us-
canadian border-geneva-on-the-
lake to conneaut oh beyond 5 nm off shoreline to us-
canadian border-
conneaut oh to ripley ny beyond 5 nm off shoreline to us-
canadian border-
344 am edt mon aug 17 2026

.today...northwest winds 15 to 20 knots becoming west 5 to
15 knots. a slight chance of showers early. waves 1 to 3 feet. 
.tonight...northwest winds 5 to 15 knots becoming north less than
10 knots. waves 2 feet or less. 
.tuesday...north winds 10 knots or less becoming west. waves
2 feet or less. 
.tuesday night...southwest winds 10 to 15 knots. showers likely
overnight. waves 1 to 3 feet. 
.wednesday...west winds 5 to 15 knots becoming northeast. showers
likely during the day. waves 1 to 3 feet subsiding to 1 foot or
less. 
.thursday...northeast winds 5 to 10 knots becoming east. waves
1 foot or less. 
.friday...east winds less than 10 knots becoming southeast. waves
1 foot or less. 

$$

fzus61 kcle 170744
glfle 
expires:202608171415;;335999

open lake forecast for lake erie
national weather service cleveland oh
344 am edt mon aug 17 2026

for waters beyond five nautical miles of shore on lake erie

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...
high pressure 30.00 inches will build from the north today and 
move south of the lake on tuesday. a cold front will cross the 
lake on wednesday. high pressure 30.20 inches will build back over
the lake on thursday and friday.


lez162>164-171415-
detroit river lt. to maumee bay oh to reno beach oh beyond 5nm
offshoreline to us-canadian border-
reno beach to the islands oh beyond 5nm off shoreline to us-
canadian border-
the islands to vermilion oh beyond 5 nm off shoreline to us-
canadian border-
344 am edt mon aug 17 2026

.today...north winds 5 to 15 knots becoming northwest less than
10 knots. a slight chance of showers this morning. waves 2 feet
or less. 
.tonight...north winds 10 knots or less becoming northwest. waves
1 foot or less. 
.tuesday...west winds 5 to 10 knots becoming southwest. waves
1 foot or less. 
.tuesday night...southwest winds 5 to 15 knots. a chance of
showers overnight. waves 1 to 2 feet. 
.wednesday...west winds 5 to 15 knots becoming northeast. a
chance of showers during the day. waves 2 feet or less. 
.thursday...northeast winds 5 to 10 knots becoming east. waves
1 foot or less. 
.friday...east winds 10 knots or less becoming south. waves
1 foot or less. 

$$

fzus63 kdtx 170738
glfsc 
expires:202608171545;;335824

lake st clair forecast
national weather service detroit/pontiac mi
338 am edt mon aug 17 2026

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 area of low pressure, 29.80 inches, is tracking
east across ontario this afternoon and will pull a cold front
across the central great lakes region late this evening. this
cold front brings in a 6- 8 hour bout of 20-25 knot northwest
winds tonight into early monday morning and chances for
thunderstorms this afternoon and evening. high pressure, 30.20
inches, builds in behind the front for monday and most of
tuesday.


lcz460-171545-
lake st clair-
338 am edt mon aug 17 2026

.today...north winds 10 to 15 knots diminishing to 5 to 10 knots in
the late morning and afternoon. partly sunny. waves 2 feet or less.
.tonight...northeast winds 5 to 10 knots this evening becoming light
and variable. mostly clear. waves 2 feet or less.
.tuesday...light and variable winds becoming southwest 5 to 10 knots
in the late morning and afternoon. mostly sunny. waves 2 feet or
less.
.tuesday night...southwest winds 10 to 15 knots. partly cloudy. a
chance of light showers ...then light showers likely after midnight.
waves 2 feet or less.
.wednesday...northwest winds 10 to 15 knots becoming northeast 5 to
10 knots in the afternoon and evening. partly cloudy. light showers
likely in the morning...then a chance of light showers in the
afternoon. waves 2 feet or less.
.thursday...east winds 5 to 10 knots. mostly clear. waves 2 feet or
less.
.friday...south winds 5 to 10 knots. clear. waves 2 feet or less.

$$

fzus63 kdtx 170738
glflh 
expires:202608171545;;335820

open lake forecast for lake huron
national weather service detroit/pontiac mi
338 am edt mon aug 17 2026

for waters beyond five nautical miles off shore on lake huron

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 area of low pressure, 29.80 inches, is tracking
east across ontario this afternoon and will pull a cold front
across the central great lakes region late this evening. this
cold front brings in a 6- 8 hour bout of 20-25 knot northwest
winds tonight into early monday morning and chances for
thunderstorms this afternoon and evening. high pressure, 30.20
inches, builds in behind the front for monday and most of
tuesday.


lhz361-171545-
lake huron from 5nm east of mackinac bridge to presque isle lt
beyond 5 nm off shore-
338 am edt mon aug 17 2026

.today...northwest winds 5 to 10 knots backing to the west in the
afternoon. waves 1 to 3 feet. 
.tonight...west winds 5 to 10 knots early in the evening becoming
light and variable...then becoming southwest 5 to 10 knots early
in the morning. waves 2 feet or less. 
.tuesday...southwest winds 10 to 15 knots veering to the west
early in the afternoon. a chance of showers and thunderstorms in
the afternoon. waves 1 to 3 feet. 
.tuesday night...northwest winds 10 to 15 knots decreasing to
5 to 10 knots after midnight. a chance of showers. waves 1 to
3 feet. 
.wednesday...northwest winds 5 to 10 knots increasing to 10 to
15 knots late in the morning...then decreasing to 5 to 10 knots
late in the evening. waves 1 to 3 feet. 
.thursday...northwest winds 5 to 10 knots backing to the west
early in the evening...then veering to the west 5 to 10 knots by
midnight. waves 2 feet or less. 
.friday...south winds 5 to 10 knots. a chance of showers by
midnight. waves 2 feet or less. 


$$

fzus63 kdtx 170738
glflh 
expires:202608171545;;335821

open lake forecast for lake huron
national weather service detroit/pontiac mi
338 am edt mon aug 17 2026

for waters beyond five nautical miles off shore on lake huron

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 area of low pressure, 29.80 inches, is tracking
east across ontario this afternoon and will pull a cold front
across the central great lakes region late this evening. this
cold front brings in a 6- 8 hour bout of 20-25 knot northwest
winds tonight into early monday morning and chances for
thunderstorms this afternoon and evening. high pressure, 30.20
inches, builds in behind the front for monday and most of
tuesday.


lhz362-363-171545-
lake huron from presque isle light to sturgeon point mi beyond
5nm off shore-
lake huron from sturgeon point to alabaster mi beyond 5nm off
shore-
338 am edt mon aug 17 2026

.today...northwest winds 10 to 15 knots. waves 3 to 5 feet
subsiding to 1 to 3 feet in the afternoon. 
.tonight...light and variable winds becoming southwest 5 to
10 knots early in the morning. waves 2 feet or less. 
.tuesday...southwest winds 5 to 10 knots increasing to 10 to
15 knots in the late morning and afternoon. a chance of showers
in the afternoon. waves 1 to 3 feet. 
.tuesday night...south winds 5 to 10 knots veering to the west by
midnight...then becoming northwest 10 to 15 knots after midnight.
a chance of showers and thunderstorms in the evening...then a
chance of showers after midnight. waves 1 to 3 feet. 
.wednesday...northwest winds 5 to 10 knots. waves 1 to 3 feet. 
.thursday...northwest winds 5 to 10 knots veering to the east by
midnight. waves 2 feet or less. 
.friday...south winds 5 to 10 knots increasing to 10 to 15 knots
. waves 1 to 3 feet. 


$$

fzus63 kdtx 170738
glflh 
expires:202608171545;;335822

open lake forecast for lake huron
national weather service detroit/pontiac mi
338 am edt mon aug 17 2026

for waters beyond five nautical miles off shore on lake huron

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 area of low pressure, 29.80 inches, is tracking
east across ontario this afternoon and will pull a cold front
across the central great lakes region late this evening. this
cold front brings in a 6- 8 hour bout of 20-25 knot northwest
winds tonight into early monday morning and chances for
thunderstorms this afternoon and evening. high pressure, 30.20
inches, builds in behind the front for monday and most of
tuesday.


lhz462>464-171545-
lake huron from port austin to harbor beach beyond 5nm off shore-
lake huron from harbor beach to port sanilac beyond 5nm off shore-
lake huron from port sanilac to port huron beyond 5nm off shore-
338 am edt mon aug 17 2026

.today...north winds 10 to 15 knots decreasing to 5 to 10 knots
late in the afternoon. waves 3 to 5 feet subsiding to 2 to 4 feet
late in the afternoon. 
.tonight...north winds 5 to 10 knots early in the evening
becoming light and variable. waves 2 feet or less. 
.tuesday...southwest winds 5 to 10 knots. waves 2 feet or less. 
.tuesday night...south winds 5 to 10 knots becoming west 10 to
15 knots in the late evening and overnight. showers and a chance
of thunderstorms in the evening...then showers likely after
midnight. waves 1 to 3 feet. 
.wednesday...northwest winds 10 to 15 knots becoming north 5 to
10 knots late in the morning...then veering to the northeast late
in the evening. waves 2 feet or less. 
.thursday...north winds 5 to 10 knots veering to the northeast by
midnight. waves 2 feet or less. 
.friday...southeast winds 5 to 10 knots becoming south 10 to
15 knots by midnight. waves 2 feet or less. 


$$

fzus63 kmkx 170801
glflm 
expires:202608171530;;336409

open lake forecast for lake michigan
national weather service milwaukee/sullivan wi
301 am cdt mon aug 17 2026

for waters beyond five nautical miles of shore on lake michigan.

waves are provided as a range of significant wave heights, which
is the average of the highest 1/3 of the wave, along with the
average height of the highest 10% of the waves which will
occasionally be encountered.

.synopsis...

high pressure around 30.1 inches will build east from the plains 
today, bringing light and variable winds to lake michigan through 
tonight. the high pressure will pass to the south of lake 
michigan on tuesday and bringing increasing southwesterly winds 
through the day as a low pressure around 29.5 inches develops and
meanders over the hudson bay region. this low pressure will then 
drag a slow moving cold front across the upper great lakes later 
tuesday into early wednesday and bring thunderstorm chances back 
to the region. the front is progged to push east of the region by 
wednesday with another high pressure building back into the 
region for the second half of the week along with light and 
variable winds. increasing southwesterly winds are expected to 
return for the end of the week along with additional thunderstorm
chances.


lmz080-669-671-673-675-777-779-870-872-874-876-878-171530-
lake michigan from michigan city in to st. joseph mi 5 nm
offshore to mid lake-
lake michigan from sheboygan to port washington wi 5 nm offshore
to mid lake-
lake michigan from port washington to north point light wi 5 nm
offshore to mid lake-
lake michigan from north point light to wind point wi 5 nm
offshore to mid lake-
lake michigan from wind point wi to winthrop harbor il 5 nm
offshore to mid lake-
lake michigan from winthrop harbor to wilmette harbor il 5 nm
offshore to mid lake-
lake michigan from wilmette harbor il to michigan city in 5 nm
offshore to mid lake-
lake michigan from whitehall to pentwater mi 5 nm offshore to mid
lake-
lake michigan from grand haven to whitehall mi 5 nm offshore to
mid lake-
lake michigan from holland to grand haven mi 5 nm offshore to mid
lake-
lake michigan from south haven to holland mi 5 nm offshore to mid
lake-
lake michigan from st. joseph to south haven mi 5 nm offshore to
mid lake-
301 am cdt mon aug 17 2026

sheboygan wi to pentwater mi south...

.today...north winds 10 to 15 kt increasing to 10 to 20 kt. waves
1 to 3 ft. 
.tonight...southwest winds 10 to 15 kt becoming west 10 to 20 kt.
waves 1 to 3 ft. 
.tuesday...west winds 10 to 20 kt becoming southwest 15 to 25 kt.
chance of showers in the afternoon. waves 2 to 4 ft. 
.tuesday night...west winds 10 to 20 kt becoming northwest.
chance of showers and thunderstorms in the evening, then chance
of showers overnight. waves 2 to 4 ft. 
.wednesday...north winds 10 to 15 kt increasing to 10 to 20 kt.
waves 1 to 3 ft. 
.wednesday night...northeast winds 10 to 20 kt diminishing to
5 to 10 kt. waves 1 to 2 ft. 
.thursday...northeast winds 5 to 10 kt increasing to 10 to 15 kt.
waves 1 to 2 ft. 
.friday...south winds 10 to 20 kt increasing to 15 to 25 kt.
waves 1 to 2 ft building to 2 to 4 ft.  

$$

fzus63 kmkx 170801
glflm 
expires:202608171530;;336408

open lake forecast for lake michigan
national weather service milwaukee/sullivan wi
301 am cdt mon aug 17 2026

for waters beyond five nautical miles of shore on lake michigan.

waves are provided as a range of significant wave heights, which
is the average of the highest 1/3 of the wave, along with the
average height of the highest 10% of the waves which will
occasionally be encountered.

.synopsis...

high pressure around 30.1 inches will build east from the plains 
today, bringing light and variable winds to lake michigan through 
tonight. the high pressure will pass to the south of lake 
michigan on tuesday and bringing increasing southwesterly winds 
through the day as a low pressure around 29.5 inches develops and
meanders over the hudson bay region. this low pressure will then 
drag a slow moving cold front across the upper great lakes later 
tuesday into early wednesday and bring thunderstorm chances back 
to the region. the front is progged to push east of the region by 
wednesday with another high pressure building back into the 
region for the second half of the week along with light and 
variable winds. increasing southwesterly winds are expected to 
return for the end of the week along with additional thunderstorm
chances.


lmz261-362-364-366-563-565-567-868-171530-
lake michigan from seul choix point to rock island passage 5 nm
offshore to mid lake-
lake michigan south of a line from seul choix point to the
mackinac bridge and north of a line from charlevoix mi to south
fox island 5 nm offshore-
lake michigan from charlevoix to point betsie mi 5 nm offshore to
mid lake-
lake michigan from point betsie to manistee mi 5 nm offshore to
mid lake-
lake michigan from rock island passage to sturgeon bay wi-
lake michigan from sturgeon bay to two rivers wi 5 nm offshore to
mid lake-
lake michigan from two rivers to sheboygan wi 5 nm offshore to
mid lake-
lake michigan from pentwater to manistee mi 5 nm offshore to mid
lake-
301 am cdt mon aug 17 2026

sheboygan wi to pentwater mi north...

.today...northwest winds 5 to 10 kt becoming west late this
morning, then becoming southwest 10 to 20 kt this afternoon.
waves 1 to 2 ft. 
.tonight...south winds 10 to 15 kt becoming southwest 10 to
20 kt. waves 1 to 3 ft. 
.tuesday...west winds 10 to 20 kt increasing to 15 to 25 kt.
chance of showers in the morning, then chance of showers and
thunderstorms in the afternoon. waves 2 to 4 ft. 
.tuesday night...northwest winds 10 to 20 kt becoming north 10 to
15 kt. chance of showers and thunderstorms in the evening, then
chance of showers overnight. waves 2 to 4 ft subsiding to 1 to
3 ft. 
.wednesday...northwest winds 10 to 15 kt increasing to 10 to
20 kt. waves 1 to 2 ft. 
.wednesday night...east winds 10 to 15 kt becoming northeast.
waves 1 to 2 ft. 
.thursday...northeast winds 5 to 10 kt veering to southeast 10 to
20 kt. waves 1 ft or less. 
.friday...southwest winds 15 to 25 kt increasing to 30 kt. waves
2 to 4 ft.  

$$

fzus63 kmqt 170801
glfls 
expires:202608172000;;336431

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon aug 17 2026

for waters beyond 5 nautical miles of shore on lake superior.

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 30.1 inch high pressure expands over the midwest this morning, 
extending a 30.0 inch ridge over lake superior. this high weakens to 
30.0 inches throughout today and shifts south as a 29.8 inch trough, 
associated with a 29.6 inch low over the hudson bay, deepens over 
lake superior. troughing lingers until tuesday afternoon when weak 
29.9 inch ridging returns to lake superior. 30.0 inch high pressure 
settles over the northern plains tuesday afternoon and night, 
eventually moving over lake superior wednesday evening before 
expanding to cover much of the great lakes by thursday afternoon. 
friday into the weekend, a low pressure of around 29.8 inches 
transits across northern ontario quickly followed by 30.2 inch 
ridging for the latter part of the weekend into next week.




lsz162-172000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 am edt mon aug 17 2026 /301 am cdt mon aug 17 2026/

.early this morning...west winds 5 to 15 knots. waves calm to
2 feet. 
.today...west winds 5 to 15 knots becoming southwest 10 to
20 knots in the afternoon. waves building to 1 to 3 feet. 
.tonight...west winds 10 to 20 knots. a chance of showers and a
slight chance of thunderstorms through midnight. waves subsiding
to calm to 2 feet. 
.tuesday...west winds 5 to 15 knots becoming southwest 10 to
20 knots late. waves calm to 2 feet. 
.tuesday night...west winds 5 to 15 knots becoming northwest
10 to 20 knots after midnight. waves calm to 2 feet. 
.wednesday...northwest winds 5 to 15 knots backing southwest by
mid afternoon. waves calm to 2 feet. 
.wednesday night...south winds 5 to 15 knots becoming north less
than 10 knots after midnight. waves calm to 2 feet. 
.thursday...south winds 5 to 15 knots veering southwest. a chance
of showers. waves calm to 2 feet. 
.friday...southwest winds 10 to 20 knots veering northwest. a
chance of showers. waves calm to 2 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202608172000;;336432

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon aug 17 2026

for waters beyond 5 nautical miles of shore on lake superior.

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 30.1 inch high pressure expands over the midwest this morning, 
extending a 30.0 inch ridge over lake superior. this high weakens to 
30.0 inches throughout today and shifts south as a 29.8 inch trough, 
associated with a 29.6 inch low over the hudson bay, deepens over 
lake superior. troughing lingers until tuesday afternoon when weak 
29.9 inch ridging returns to lake superior. 30.0 inch high pressure 
settles over the northern plains tuesday afternoon and night, 
eventually moving over lake superior wednesday evening before 
expanding to cover much of the great lakes by thursday afternoon. 
friday into the weekend, a low pressure of around 29.8 inches 
transits across northern ontario quickly followed by 30.2 inch 
ridging for the latter part of the weekend into next week.




lsz263-172000-
lake superior from saxon harbor wi to upper entrance to portage
canal mi 5nm off shore to the us/canadian border including isle
royale national park-
401 am edt mon aug 17 2026

.early this morning...west winds 5 to 15 knots. waves calm to
2 feet. 
.today...west winds 5 to 15 knots becoming southwest 15 to
25 knots in the afternoon. waves building to 2 to 4 feet. 
.tonight...southwest winds 15 to 25 knots becoming west 10 to
20 knots after midnight. a slight chance of thunderstorms through
midnight. a slight chance of showers. waves subsiding to calm to
2 feet. 
.tuesday...northwest winds 10 to 20 knots backing southwest late.
waves building to 1 to 3 feet. 
.tuesday night...west winds 10 to 20 knots becoming northwest
5 to 15 knots after midnight. waves subsiding to calm to 2 feet. 
.wednesday...northwest winds 5 to 15 knots backing southwest by
mid afternoon. waves calm to 2 feet. 
.wednesday night...southwest winds 5 to 15 knots becoming south
less than 10 knots after midnight. waves calm to 2 feet. 
.thursday...southwest winds 10 to 20 knots backing south. a
chance of showers. waves calm to 2 feet. 
.friday...southwest winds 10 to 20 knots becoming west 5 to
15 knots. a chance of showers. waves building to 1 to 3 feet,
then subsiding to calm to 2 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202608172000;;336433

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon aug 17 2026

for waters beyond 5 nautical miles of shore on lake superior.

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 30.1 inch high pressure expands over the midwest this morning, 
extending a 30.0 inch ridge over lake superior. this high weakens to 
30.0 inches throughout today and shifts south as a 29.8 inch trough, 
associated with a 29.6 inch low over the hudson bay, deepens over 
lake superior. troughing lingers until tuesday afternoon when weak 
29.9 inch ridging returns to lake superior. 30.0 inch high pressure 
settles over the northern plains tuesday afternoon and night, 
eventually moving over lake superior wednesday evening before 
expanding to cover much of the great lakes by thursday afternoon. 
friday into the weekend, a low pressure of around 29.8 inches 
transits across northern ontario quickly followed by 30.2 inch 
ridging for the latter part of the weekend into next week.




lsz264-172000-
lake superior from upper entrance to portage canal to manitou
island mi 5nm off shore to the us/canadian border-
401 am edt mon aug 17 2026

.early this morning...west winds 5 to 15 knots. waves calm to
2 feet. 
.today...west winds 5 to 15 knots becoming southwest 10 to
20 knots in the afternoon. waves building to 2 to 4 feet. 
.tonight...southwest winds 10 to 20 knots veering west late. a
chance of showers. waves subsiding to calm to 2 feet, then
building to 1 to 3 feet. 
.tuesday...northwest winds 10 to 20 knots backing west in the
afternoon. waves subsiding to calm to 2 feet. 
.tuesday night...west winds 10 to 20 knots becoming northwest
5 to 15 knots after midnight. waves building to 1 to 3 feet, then
subsiding to calm to 2 feet. 
.wednesday...northwest winds 5 to 15 knots backing west by mid
afternoon. waves calm to 2 feet. 
.wednesday night...southwest winds 5 to 15 knots diminishing to
less than 10 knots after midnight. waves calm to 2 feet. 
.thursday...southwest winds 5 to 15 knots becoming south 10 to
20 knots. a chance of showers. waves calm to 2 feet. 
.friday...southwest winds 10 to 20 knots becoming west 5 to
15 knots. a chance of showers. waves building to 1 to 3 feet,
then subsiding to calm to 2 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202608172000;;336434

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon aug 17 2026

for waters beyond 5 nautical miles of shore on lake superior.

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 30.1 inch high pressure expands over the midwest this morning, 
extending a 30.0 inch ridge over lake superior. this high weakens to 
30.0 inches throughout today and shifts south as a 29.8 inch trough, 
associated with a 29.6 inch low over the hudson bay, deepens over 
lake superior. troughing lingers until tuesday afternoon when weak 
29.9 inch ridging returns to lake superior. 30.0 inch high pressure 
settles over the northern plains tuesday afternoon and night, 
eventually moving over lake superior wednesday evening before 
expanding to cover much of the great lakes by thursday afternoon. 
friday into the weekend, a low pressure of around 29.8 inches 
transits across northern ontario quickly followed by 30.2 inch 
ridging for the latter part of the weekend into next week.




lsz265-172000-
lake superior west of line from manitou island to marquette mi
beyond 5nm from shore-
401 am edt mon aug 17 2026

.early this morning...west winds 10 to 20 knots. waves calm to
2 feet. 
.today...west winds 10 to 20 knots backing southwest late. waves
calm to 2 feet. 
.tonight...south winds 10 to 20 knots becoming southwest 15 to
25 knots after midnight, then veering west late. a slight chance
of showers. waves building to 1 to 3 feet. 
.tuesday...west winds 15 to 25 knots becoming northwest 20 to
30 knots in the afternoon, then becoming west 15 to 25 knots
late. waves subsiding to calm to 2 feet. 
.tuesday night...west winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. waves calm to 2 feet. 
.wednesday...northwest winds 10 to 20 knots becoming north 5 to
15 knots by mid afternoon. waves calm to 2 feet. 
.wednesday night...southwest winds 5 to 15 knots. waves calm to
2 feet. 
.thursday...southeast winds 5 to 15 knots becoming south 10 to
20 knots. waves calm to 2 feet. 
.friday...west winds 10 to 20 knots increasing to 15 to 25 knots.
a chance of showers. waves calm to 2 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202608172000;;336435

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon aug 17 2026

for waters beyond 5 nautical miles of shore on lake superior.

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 30.1 inch high pressure expands over the midwest this morning, 
extending a 30.0 inch ridge over lake superior. this high weakens to 
30.0 inches throughout today and shifts south as a 29.8 inch trough, 
associated with a 29.6 inch low over the hudson bay, deepens over 
lake superior. troughing lingers until tuesday afternoon when weak 
29.9 inch ridging returns to lake superior. 30.0 inch high pressure 
settles over the northern plains tuesday afternoon and night, 
eventually moving over lake superior wednesday evening before 
expanding to cover much of the great lakes by thursday afternoon. 
friday into the weekend, a low pressure of around 29.8 inches 
transits across northern ontario quickly followed by 30.2 inch 
ridging for the latter part of the weekend into next week.




lsz266-172000-
lake superior east of a line from manitou island to marquette mi
and west of a line from grand marais mi to the us/canadian border
beyond 5nm from shore-
401 am edt mon aug 17 2026

.early this morning...west winds 10 to 20 knots. waves calm to
2 feet. 
.today...west winds 10 to 20 knots diminishing to 5 to 15 knots
in the afternoon, then backing southwest late. waves calm to
2 feet. 
.tonight...south winds 5 to 15 knots increasing to 10 to 20 knots
after midnight, then becoming west 15 to 25 knots late. a slight
chance of showers after midnight. waves building to 1 to 3 feet. 
.tuesday...west winds 15 to 25 knots veering northwest in the
afternoon, then becoming west 10 to 20 knots late. a slight
chance of showers through early afternoon. waves building to 2 to
4 feet, then subsiding to calm to 2 feet. 
.tuesday night...west winds 10 to 20 knots veering northwest
after midnight. waves calm to 2 feet. 
.wednesday...northwest winds 5 to 15 knots. waves calm to 2 feet.
.wednesday night...northwest winds 5 to 15 knots backing west
after midnight. waves calm to 2 feet. 
.thursday...southwest winds 5 to 15 knots becoming south 10 to
20 knots. waves calm to 2 feet. 
.friday...south winds 10 to 20 knots veering southwest. a chance
of showers. waves building to 1 to 3 feet, then subsiding to calm
to 2 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202608172000;;336436

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon aug 17 2026

for waters beyond 5 nautical miles of shore on lake superior.

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 30.1 inch high pressure expands over the midwest this morning, 
extending a 30.0 inch ridge over lake superior. this high weakens to 
30.0 inches throughout today and shifts south as a 29.8 inch trough, 
associated with a 29.6 inch low over the hudson bay, deepens over 
lake superior. troughing lingers until tuesday afternoon when weak 
29.9 inch ridging returns to lake superior. 30.0 inch high pressure 
settles over the northern plains tuesday afternoon and night, 
eventually moving over lake superior wednesday evening before 
expanding to cover much of the great lakes by thursday afternoon. 
friday into the weekend, a low pressure of around 29.8 inches 
transits across northern ontario quickly followed by 30.2 inch 
ridging for the latter part of the weekend into next week.




lsz267-172000-
lake superior from grand marais mi to whitefish point mi 5nm off
shore to the us/canadian border-
401 am edt mon aug 17 2026

.early this morning...northwest winds 5 to 15 knots. waves 1 to
3 feet subsiding to calm to 2 feet. 
.today...west winds 5 to 15 knots increasing to 10 to 20 knots in
the afternoon, then becoming southwest 5 to 15 knots late. waves
calm to 2 feet. 
.tonight...south winds 5 to 15 knots becoming southwest 10 to
20 knots late. a slight chance of showers after midnight. waves
building to 1 to 3 feet. 
.tuesday...west winds 10 to 20 knots. a chance of showers. a
slight chance of thunderstorms by mid afternoon. waves 1 to
3 feet. 
.tuesday night...west winds 10 to 20 knots. waves subsiding to
calm to 2 feet. 
.wednesday...northwest winds 10 to 20 knots. waves calm to
2 feet. 
.wednesday night...northwest winds 5 to 15 knots. waves calm to
2 feet. 
.thursday...west winds 5 to 15 knots backing south. waves calm to
2 feet. 
.friday...southwest winds 10 to 20 knots. a chance of showers.
waves building to 1 to 3 feet, then subsiding to calm to 2 feet. 

$$