fzus63 kdtx 181933
glflh 
expires:202604190400;;597253

open lake forecast for lake huron
national weather service detroit/pontiac mi
333 pm edt sat apr 18 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...colder air filters into the region this weekend,
maintaining gusty northwesterly winds. a secondary cold front
passes across the region on sunday, then high pressure settles in
on monday. milder southerly flow early tuesday precedes the next
cold front set to pass through late tuesday.


lhz361>363-190400-
lake huron from 5nm east of mackinac bridge to presque isle lt
beyond 5 nm off shore-
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-
333 pm edt sat apr 18 2026

.tonight...west winds 10 to 15 knots becoming southwest 5 to
10 knots early in the morning. waves 4 to 6 feet. waves
occasionally around 8 feet. 
.sunday...southwest winds 10 to 15 knots becoming west 15 to
20 knots early in the afternoon...then becoming northwest 20 to
25 knots with gusts to around 30 knots late in the afternoon.
waves 4 to 6 feet building to 6 to 9 feet late in the afternoon.
waves occasionally around 12 feet. 
.sunday night...northwest winds 20 to 25 knots with gusts to
around 30 knots decreasing to 15 to 20 knots after midnight.
waves 8 to 12 feet. waves occasionally around 15 feet. 
.monday...northwest winds 10 to 15 knots decreasing to 5 to
10 knots in the late morning and afternoon. waves 4 to 6 feet
subsiding to 2 to 4 feet early in the afternoon. waves
occasionally around 8 feet. 
.monday night...southeast winds 10 to 15 knots becoming south
15 to 20 knots in the late evening and overnight. waves 1 to
3 feet building to 4 to 6 feet in the late evening and overnight.
waves occasionally around 8 feet. 
.tuesday...south winds 20 to 25 knots with gusts to around
30 knots decreasing to 15 to 20 knots late in the morning...then
decreasing to 10 to 15 knots late in the afternoon veering to the
northwest late in the evening. waves 6 to 9 feet subsiding to
3 to 5 feet late in the evening. waves occasionally around
12 feet. 
.wednesday...north winds 10 to 15 knots becoming northeast 5 to
10 knots in the late morning and early afternoon...then becoming
light and variable early in the evening becoming east 5 to
10 knots by midnight. waves 2 to 4 feet subsiding to 1 to 3 feet.
.thursday...southeast winds 5 to 10 knots increasing to 15 to
20 knots. waves 1 to 3 feet building to 5 to 7 feet. waves
occasionally around 10 feet. 


$$

fzus63 kdtx 181933
glflh 
expires:202604190400;;597254

open lake forecast for lake huron
national weather service detroit/pontiac mi
333 pm edt sat apr 18 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...colder air filters into the region this weekend,
maintaining gusty northwesterly winds. a secondary cold front
passes across the region on sunday, then high pressure settles in
on monday. milder southerly flow early tuesday precedes the next
cold front set to pass through late tuesday.


lhz462>464-190400-
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-
333 pm edt sat apr 18 2026

.tonight...west winds 5 to 10 knots increasing to 10 to 15 knots
by midnight...then decreasing to 5 to 10 knots early in the
morning. waves 1 to 3 feet. 
.sunday...west winds 5 to 10 knots increasing to 10 to 15 knots
in the late morning and early afternoon...then veering to the
west 10 to 15 knots late in the afternoon. a chance of showers in
the afternoon. waves 1 to 3 feet building to 2 to 4 feet late in
the afternoon. 
.sunday night...northwest winds 15 to 20 knots. waves 6 to
9 feet. waves occasionally around 12 feet. 
.monday...northwest winds 15 to 20 knots decreasing to 5 to
10 knots. waves 4 to 6 feet. waves occasionally around 8 feet. 
.monday night...east winds 5 to 10 knots becoming south 10 to
15 knots by midnight...then increasing to 15 to 20 knots after
midnight. waves 1 to 3 feet building to 4 to 6 feet after
midnight. waves occasionally around 8 feet. 
.tuesday...south winds 20 to 25 knots with gusts to around
30 knots decreasing to 15 to 20 knots late in the morning...then
decreasing to 10 to 15 knots late in the afternoon veering to the
northwest late in the evening. waves 4 to 6 feet subsiding to
2 to 4 feet late in the evening. waves occasionally around
8 feet. 
.wednesday...north winds 10 to 15 knots becoming light and
variable. waves 1 to 3 feet. 
.thursday...southeast winds 5 to 10 knots increasing to 10 to
15 knots . waves 1 to 3 feet building to 2 to 4 feet by midnight.


$$

fzus63 kmkx 181943
glflm 
expires:202604190315;;597491

open lake forecast for lake michigan
national weather service milwaukee/sullivan wi
243 pm cdt sat apr 18 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...

breezy west northwest winds are expected into tonight, as strong 
low pressure around 29.0 inches continues to move well to the 
northeast of the region, with high pressure around 30.2 inches 
over south central canada. 

the high will move southeast across the region sunday into 
monday, with winds gradually weakening. as the high shifts east 
monday night into tuesday, breezy southerly winds should develop 
over the region.

high pressure around 30.2 inches will pass by to the northeast of
the region wednesday, with winds weakening. winds should become 
southeast to south and increase later in the week, as strong low 
pressure around 29.2 inches develops in the northern plains.


lmz261-362-364-366-563-565-567-868-190315-
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-
243 pm cdt sat apr 18 2026

sheboygan wi to pentwater mi north...

.tonight...west winds to 30 kt diminishing to 10 to 20 kt. waves
4 to 6 ft occasionally to 8 ft subsiding to 3 to 5 ft. 
.sunday...northwest winds 15 to 25 kt becoming north. waves 2 to
4 ft. 
.sunday night...north winds 15 to 25 kt diminishing to 10 to
15 kt. waves 3 to 5 ft subsiding to 1 to 3 ft. 
.monday...west winds 10 to 15 kt becoming south 15 to 25 kt in
the afternoon. waves 1 to 3 ft building to 2 to 4 ft. 
.monday night...south winds to 30 kt. waves 5 to 8 ft
occasionally to 10 ft. 
.tuesday...southwest winds to 30 kt diminishing to 10 to 20 kt in
the afternoon. waves 5 to 8 ft occasionally to 10 ft subsiding to
4 to 6 ft occasionally to 8 ft. 
.tuesday night...northeast winds 10 to 15 kt. waves 3 to 5 ft
subsiding to 1 to 3 ft. 
.wednesday...northeast winds 10 to 15 kt diminishing to 5 to
10 kt. waves 1 to 3 ft. 
.thursday...south winds 15 to 25 kt. waves 4 to 6 ft occasionally
to 8 ft building to 5 to 8 ft occasionally to 10 ft.  

$$

fzus63 kmkx 181943
glflm 
expires:202604190315;;597492

open lake forecast for lake michigan
national weather service milwaukee/sullivan wi
243 pm cdt sat apr 18 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...

breezy west northwest winds are expected into tonight, as strong 
low pressure around 29.0 inches continues to move well to the 
northeast of the region, with high pressure around 30.2 inches 
over south central canada. 

the high will move southeast across the region sunday into 
monday, with winds gradually weakening. as the high shifts east 
monday night into tuesday, breezy southerly winds should develop 
over the region.

high pressure around 30.2 inches will pass by to the northeast of
the region wednesday, with winds weakening. winds should become 
southeast to south and increase later in the week, as strong low 
pressure around 29.2 inches develops in the northern plains.


lmz080-669-671-673-675-777-779-870-872-874-876-878-190315-
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-
243 pm cdt sat apr 18 2026

sheboygan wi to pentwater mi south...

.tonight...west winds 15 to 25 kt diminishing to 10 to 20 kt.
waves 4 to 6 ft occasionally to 8 ft. 
.sunday...west winds 10 to 20 kt becoming northwest. chance of
rain showers and slight chance of snow showers in the morning,
then chance of rain showers in the afternoon. waves 3 to 5 ft. 
.sunday night...north winds 10 to 20 kt diminishing to 10 to
15 kt late in the evening, then becoming northeast after midnight
diminishing to 5 to 10 kt late. waves 2 to 4 ft. 
.monday...east winds 5 to 10 kt becoming southeast 10 to 20 kt in
the afternoon. waves 1 to 3 ft building to 2 to 4 ft. 
.monday night...southeast winds 15 to 25 kt becoming south to
30 kt. waves 4 to 7 ft occasionally to 9 ft. 
.tuesday...south winds 15 to 25 kt diminishing to 10 to 20 kt.
waves 4 to 7 ft occasionally to 9 ft. 
.tuesday night...west winds 10 to 15 kt veering to north. waves
2 to 4 ft. 
.wednesday...northeast winds 10 to 15 kt becoming north 5 to
10 kt. waves 1 to 3 ft. 
.thursday...south winds 15 to 25 kt. waves 4 to 6 ft occasionally
to 8 ft building to 4 to 7 ft occasionally to 9 ft.  

$$

fzus63 kmqt 182001
glfls 
expires:202604190800;;597861

open lake forecast for lake superior
national weather service marquette mi
400 pm edt sat apr 18 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...

ridging builds over lake superior, strengthening to about 30.3 
inches sunday night into monday morning. this ridging gives way to 
29.8 inch troughing monday night into tuesday morning as a weakening 
low swings from the hudson bay shoreline of far northern ontario 
towards northern quebec. high pressure ridging builds back to 30.0 
inches over lake superior by tuesday night. the high shifts east on 
wednesday as a 29.2 inch low pressure develops over the northern 
plains. the low deepens to 29.1 inches on thursday over north 
dakota, then likely moves northeast to northern ontario through 
friday. this sends a 29.5 inch trough across the lake.



lsz162-190800-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 pm edt sat apr 18 2026 /300 pm cdt sat apr 18 2026/

.late this afternoon...west winds to 30 knots with a few gale
force gusts to 35 knots possible. waves 4 to 7 feet occasionally
to 9 feet. 
.tonight...west winds 20 to 30 knots becoming northwest 15 to
25 knots after midnight. waves subsiding to 2 to 4 feet. 
.sunday...northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. waves subsiding to calm to 2 feet. 
.sunday night...northwest winds 10 to 20 knots becoming north
5 to 15 knots after midnight. waves calm to 2 feet. 
.monday...south winds 10 to 20 knots. waves building to 2 to
4 feet. 
.monday night...southwest winds 15 to 25 knots becoming west
10 to 20 knots after midnight. waves subsiding to calm to 2 feet.
.tuesday...west winds 5 to 15 knots backing southwest by mid
afternoon. waves calm to 2 feet. 
.tuesday night...northeast winds 5 to 15 knots. waves calm to
2 feet. 
.wednesday...east winds 5 to 15 knots increasing to 10 to
20 knots. a chance of rain showers. waves building to 3 to 6 feet
occasionally to 8 feet. 
.thursday...east winds 15 to 25 knots. a chance of rain showers,
then rain showers likely. waves subsiding to 3 to 5 feet
occasionally to 7 feet, then building to 6 to 9 feet occasionally
to 11 feet. 

$$

fzus63 kmqt 182001
glfls 
expires:202604190800;;597862

open lake forecast for lake superior
national weather service marquette mi
400 pm edt sat apr 18 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...

ridging builds over lake superior, strengthening to about 30.3 
inches sunday night into monday morning. this ridging gives way to 
29.8 inch troughing monday night into tuesday morning as a weakening 
low swings from the hudson bay shoreline of far northern ontario 
towards northern quebec. high pressure ridging builds back to 30.0 
inches over lake superior by tuesday night. the high shifts east on 
wednesday as a 29.2 inch low pressure develops over the northern 
plains. the low deepens to 29.1 inches on thursday over north 
dakota, then likely moves northeast to northern ontario through 
friday. this sends a 29.5 inch trough across the lake.



lsz263-190800-
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-
400 pm edt sat apr 18 2026

...gale warning in effect until 8 pm edt this evening...

.late this afternoon...west gales to 35 knots. flurries. waves
8 to 11 feet occasionally to 14 feet. 
.tonight...west winds 20 to 30 knots veering northwest after
midnight, then diminishing to 15 to 25 knots late. flurries
through midnight. waves subsiding to 3 to 6 feet occasionally to
8 feet. 
.sunday...northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. waves subsiding to 1 to 3 feet. 
.sunday night...northwest winds 5 to 15 knots veering north after
midnight, then backing northwest late. waves subsiding to calm to
2 feet. 
.monday...southwest winds 10 to 20 knots becoming south 15 to
25 knots by mid afternoon. waves building to 3 to 5 feet
occasionally to 7 feet. 
.monday night...south winds 15 to 25 knots veering west after
midnight. waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 2 to 4 feet. 
.tuesday...west winds 5 to 15 knots. waves subsiding to calm to
2 feet. 
.tuesday night...east winds less than 10 knots. waves calm to
2 feet. 
.wednesday...east winds 5 to 15 knots becoming southeast 15 to
25 knots. waves building to 3 to 6 feet occasionally to 8 feet. 
.thursday...east winds 15 to 25 knots becoming southeast 20 to
30 knots. a chance of rain showers, then rain showers likely.
waves building to 7 to 10 feet occasionally to 13 feet. 

$$

fzus63 kmqt 182001
glfls 
expires:202604190800;;597863

open lake forecast for lake superior
national weather service marquette mi
400 pm edt sat apr 18 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...

ridging builds over lake superior, strengthening to about 30.3 
inches sunday night into monday morning. this ridging gives way to 
29.8 inch troughing monday night into tuesday morning as a weakening 
low swings from the hudson bay shoreline of far northern ontario 
towards northern quebec. high pressure ridging builds back to 30.0 
inches over lake superior by tuesday night. the high shifts east on 
wednesday as a 29.2 inch low pressure develops over the northern 
plains. the low deepens to 29.1 inches on thursday over north 
dakota, then likely moves northeast to northern ontario through 
friday. this sends a 29.5 inch trough across the lake.



lsz264-190800-
lake superior from upper entrance to portage canal to manitou
island mi 5nm off shore to the us/canadian border-
400 pm edt sat apr 18 2026

...gale warning in effect until midnight edt tonight...

.late this afternoon...west gales to 35 knots. flurries. waves
9 to 12 feet occasionally to 15 feet subsiding to 8 to 11 feet
occasionally to 14 feet. 
.tonight...northwest winds 20 to 30 knots. flurries through
midnight. waves subsiding to 5 to 8 feet occasionally to 10 feet.
.sunday...northwest winds 15 to 25 knots diminishing to 10 to
20 knots late. waves subsiding to 3 to 5 feet occasionally to
7 feet. 
.sunday night...northwest winds 5 to 15 knots veering north after
midnight, then backing northwest late. waves subsiding to calm to
2 feet. 
.monday...southwest winds 10 to 20 knots becoming south 15 to
25 knots by mid afternoon. waves building to 3 to 5 feet
occasionally to 7 feet. 
.monday night...south winds 15 to 25 knots veering west after
midnight. waves building to 3 to 6 feet occasionally to 8 feet. 
.tuesday...west winds 10 to 20 knots diminishing to 5 to 15 knots
by mid afternoon. waves subsiding to calm to 2 feet. 
.tuesday night...west winds less than 10 knots backing east after
midnight. waves calm to 2 feet. 
.wednesday...southeast winds 5 to 15 knots increasing to 20 to
30 knots. waves building to 3 to 6 feet occasionally to 8 feet. 
.thursday...southeast winds 20 to 30 knots increasing to gales to
35 knots. a chance of rain showers, then rain showers likely.
waves building to 8 to 11 feet occasionally to 14 feet. 

$$

fzus63 kmqt 182001
glfls 
expires:202604190800;;597864

open lake forecast for lake superior
national weather service marquette mi
400 pm edt sat apr 18 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...

ridging builds over lake superior, strengthening to about 30.3 
inches sunday night into monday morning. this ridging gives way to 
29.8 inch troughing monday night into tuesday morning as a weakening 
low swings from the hudson bay shoreline of far northern ontario 
towards northern quebec. high pressure ridging builds back to 30.0 
inches over lake superior by tuesday night. the high shifts east on 
wednesday as a 29.2 inch low pressure develops over the northern 
plains. the low deepens to 29.1 inches on thursday over north 
dakota, then likely moves northeast to northern ontario through 
friday. this sends a 29.5 inch trough across the lake.



lsz265-190800-
lake superior west of line from manitou island to marquette mi
beyond 5nm from shore-
400 pm edt sat apr 18 2026

...gale warning in effect until 8 pm edt this evening...

.late this afternoon...west gales to 40 knots. flurries. waves
6 to 9 feet occasionally to 11 feet. 
.tonight...west gales to 35 knots veering northwest after
midnight. flurries through midnight. waves subsiding to 4 to
7 feet occasionally to 9 feet. 
.sunday...northwest winds 20 to 30 knots. flurries through early
afternoon. waves subsiding to 3 to 6 feet occasionally to 8 feet.
.sunday night...northwest winds 15 to 25 knots diminishing to
5 to 15 knots. waves subsiding to calm to 2 feet. 
.monday...southwest winds 10 to 20 knots backing southeast by mid
afternoon. waves building to 1 to 3 feet. 
.monday night...south winds 20 to 30 knots veering southwest
after midnight. waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet. 
.tuesday...northwest winds 15 to 25 knots becoming north 10 to
20 knots by mid afternoon. waves subsiding to calm to 2 feet. 
.tuesday night...northwest winds 5 to 15 knots veering east after
midnight. waves calm to 2 feet. 
.wednesday...southeast winds 5 to 15 knots increasing to 15 to
25 knots. waves building to 3 to 6 feet occasionally to 8 feet. 
.thursday...southeast winds 20 to 30 knots increasing to gales to
35 knots. a chance of rain showers, then rain showers likely.
waves building to 6 to 9 feet occasionally to 11 feet. 

$$

fzus63 kmqt 182001
glfls 
expires:202604190800;;597865

open lake forecast for lake superior
national weather service marquette mi
400 pm edt sat apr 18 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...

ridging builds over lake superior, strengthening to about 30.3 
inches sunday night into monday morning. this ridging gives way to 
29.8 inch troughing monday night into tuesday morning as a weakening 
low swings from the hudson bay shoreline of far northern ontario 
towards northern quebec. high pressure ridging builds back to 30.0 
inches over lake superior by tuesday night. the high shifts east on 
wednesday as a 29.2 inch low pressure develops over the northern 
plains. the low deepens to 29.1 inches on thursday over north 
dakota, then likely moves northeast to northern ontario through 
friday. this sends a 29.5 inch trough across the lake.



lsz266-190800-
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-
400 pm edt sat apr 18 2026

...gale warning in effect until midnight edt tonight...

.late this afternoon...west gales to 35 knots. flurries. waves
10 to 14 feet occasionally to 18 feet. 
.tonight...west gales to 35 knots becoming northwest 20 to
30 knots after midnight, then increasing to gales to 35 knots
late. flurries. waves subsiding to 7 to 10 feet occasionally to
13 feet. 
.sunday...northwest gales to 35 knots diminishing to 20 to
30 knots late. a chance of snow showers. waves subsiding to 6 to
9 feet occasionally to 11 feet. 
.sunday night...northwest winds 15 to 25 knots veering north
after midnight, then diminishing to 5 to 15 knots late. waves
subsiding to 2 to 4 feet. 
.monday...southwest winds 5 to 15 knots becoming south 15 to
25 knots by mid afternoon. waves subsiding to calm to 2 feet,
then building to 2 to 4 feet. 
.monday night...south gales to 35 knots veering southwest after
midnight. waves building to 5 to 9 feet occasionally to 11 feet. 
.tuesday...west winds 15 to 25 knots becoming northwest 10 to
20 knots by mid afternoon. waves subsiding to 1 to 3 feet. 
.tuesday night...northwest winds 10 to 20 knots becoming
northeast 5 to 15 knots after midnight. waves subsiding to calm
to 2 feet. 
.wednesday...southeast winds 5 to 15 knots increasing to 20 to
30 knots. waves building to 3 to 6 feet occasionally to 8 feet. 
.thursday...southeast winds 20 to 30 knots increasing to gales to
35 knots. a chance of rain showers. waves building to 8 to
11 feet occasionally to 14 feet. 

$$

fzus63 kmqt 182001
glfls 
expires:202604190800;;597866

open lake forecast for lake superior
national weather service marquette mi
400 pm edt sat apr 18 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...

ridging builds over lake superior, strengthening to about 30.3 
inches sunday night into monday morning. this ridging gives way to 
29.8 inch troughing monday night into tuesday morning as a weakening 
low swings from the hudson bay shoreline of far northern ontario 
towards northern quebec. high pressure ridging builds back to 30.0 
inches over lake superior by tuesday night. the high shifts east on 
wednesday as a 29.2 inch low pressure develops over the northern 
plains. the low deepens to 29.1 inches on thursday over north 
dakota, then likely moves northeast to northern ontario through 
friday. this sends a 29.5 inch trough across the lake.



lsz267-190800-
lake superior from grand marais mi to whitefish point mi 5nm off
shore to the us/canadian border-
400 pm edt sat apr 18 2026

...gale warning in effect until 8 pm edt this evening...

.late this afternoon...west gales to 40 knots. flurries. waves
10 to 14 feet occasionally to 18 feet. 
.tonight...west gales to 35 knots becoming northwest 20 to
30 knots after midnight. a chance of snow showers. waves
subsiding to 7 to 10 feet occasionally to 13 feet, then building
to 8 to 11 feet occasionally to 14 feet. 
.sunday...northwest gales to 35 knots. a chance of snow showers.
waves subsiding to 6 to 9 feet occasionally to 11 feet. 
.sunday night...northwest winds 20 to 30 knots becoming north
10 to 20 knots after midnight, then diminishing to 5 to 15 knots
late. waves subsiding to 2 to 4 feet. 
.monday...west winds 5 to 15 knots becoming south 10 to 20 knots
by mid afternoon. waves subsiding to calm to 2 feet, then
building to 1 to 3 feet. 
.monday night...south gales to 35 knots. waves building to 4 to
8 feet occasionally to 10 feet. 
.tuesday...west winds 15 to 25 knots veering northwest by mid
afternoon. waves subsiding to 2 to 4 feet. 
.tuesday night...northwest winds 5 to 15 knots veering northeast
after midnight. waves subsiding to calm to 2 feet. 
.wednesday...east winds 5 to 15 knots becoming southeast 15 to
25 knots. waves building to 2 to 4 feet. 
.thursday...southeast winds 15 to 25 knots increasing to gales to
35 knots. a chance of rain showers. waves building to 6 to 9 feet
occasionally to 11 feet. 

$$