Widespread showers and thunderstorms, some severe, may produce heavy downpours and flash flooding across much of the eastern and central U.S. Dangerous heat will continue in the Pacific Northwest and expand across portions of the East. Deep tropical moisture and associated thunderstorms will bring heavy rainfall and localized flash flooding across portions of Florida into the central Gulf Coast. Read More >
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Nearshore Forecast
110
FZUS53 KDLH 161941
NSHDLH
Nearshore Marine Forecast
National Weather Service Duluth MN
241 PM CDT Wed Jul 16 2025
For waters within five 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.
LSZ140-141-170415-
Grand Portage to Grand Marais MN-
Grand Marais to Taconite Harbor MN-
241 PM CDT Wed Jul 16 2025
.TONIGHT...Northeast wind 5 to 10 knots becoming north in the
late evening and overnight. Slight chance of rain showers in the
evening. Waves 1 to 2 feet.
.THURSDAY...North wind 5 knots becoming west late in the morning,
then becoming southwest 10 to 15 knots in the afternoon. Sunny.
Waves 1 to 2 feet.
.THURSDAY NIGHT...West wind 10 to 15 knots. Partly cloudy. Waves
1 to 2 feet.
.FRIDAY...Southwest wind 5 to 10 knots. Slight chance of rain
showers in the morning, then chance of rain showers in the
afternoon. Waves 1 foot or less.
$$
LSZ142-170415-
Taconite Harbor to Silver Bay Harbor MN-
241 PM CDT Wed Jul 16 2025
.TONIGHT...North wind 5 to 10 knots easing to 5 knots after
midnight. Chance of rain showers early in the evening, then
slight chance of rain showers late in the evening. Waves 1 to
3 feet.
.THURSDAY...Northwest wind 5 knots becoming southwest in the
afternoon. Sunny. Waves 1 foot or less.
.THURSDAY NIGHT...Southwest wind 5 to 10 knots becoming west
after midnight. Partly cloudy. Waves 1 foot or less.
.FRIDAY...Southwest wind 5 knots becoming south late in the
afternoon. Chance of rain showers through the day. Slight chance
of thunderstorms in the afternoon. Waves 1 foot or less.
$$
LSZ143-144-170415-
Silver Bay Harbor to Two Harbors MN-Two Harbors to Duluth MN-
241 PM CDT Wed Jul 16 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...
.TONIGHT...Northeast wind 10 to 15 knots with gusts to around
25 knots becoming north 5 to 10 knots after midnight. Chance of
rain showers in the evening. Waves 2 to 4 feet subsiding to 1 to
2 feet after midnight.
.THURSDAY...North wind 5 to 10 knots becoming south in the
afternoon. Sunny. Waves 1 foot or less.
.THURSDAY NIGHT...Southwest wind 5 knots becoming west after
midnight. Mostly clear. Waves 1 foot or less.
.FRIDAY...Southwest wind 5 knots becoming southeast late in the
afternoon. Chance of rain showers through the day. Slight chance
of thunderstorms in the afternoon. Waves 1 foot or less.
$$
LSZ145-146-170415-
Duluth MN to Port Wing WI-Port Wing to Sand Island WI-
241 PM CDT Wed Jul 16 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...
.TONIGHT...Northeast wind 15 to 20 knots with gusts to around
25 knots becoming north 5 to 10 knots after midnight. Chance of
rain showers in the evening, then slight chance of rain showers
after midnight. Waves 3 to 5 feet subsiding to 1 to 2 feet after
midnight.
.THURSDAY...Northwest wind 5 to 10 knots becoming southwest in
the afternoon. Sunny. Waves 1 foot or less.
.THURSDAY NIGHT...South wind 5 knots. Mostly clear. Waves 1 foot
or less.
.FRIDAY...South wind 5 knots becoming southeast late in the
afternoon. Chance of rain showers through the day. Slight chance
of thunderstorms in the afternoon. Waves 1 foot or less.
$$
LSZ147-170415-
Sand Island to Bayfield WI-
241 PM CDT Wed Jul 16 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...
.TONIGHT...Northeast wind 10 to 15 knots with gusts to around
25 knots becoming north 5 knots late in the night. Chance of rain
showers in the evening, then slight chance of rain showers after
midnight. Waves 2 to 4 feet subsiding to 1 to 3 feet in the late
evening and overnight.
.THURSDAY...Northwest wind 5 knots becoming south late in the
afternoon. Sunny. Waves 1 foot or less.
.THURSDAY NIGHT...South wind 5 knots. Mostly clear. Waves 1 foot
or less.
.FRIDAY...Southwest wind 5 knots becoming southeast late in the
afternoon. Slight chance of rain showers in the morning, then
chance of rain showers and slight chance of thunderstorms in the
afternoon. Waves 1 foot or less.
$$
LSZ150-170415-
Outer Apostle Islands Beyond 5 NM from Mainland-
241 PM CDT Wed Jul 16 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...
.TONIGHT...Northeast wind 15 to 20 knots with gusts to around
25 knots becoming north 5 to 10 knots after midnight. Chance of
rain showers in the evening, then slight chance of rain showers
after midnight. Waves 3 to 5 feet subsiding to 1 to 2 feet. Waves
occasionally to 7 feet.
.THURSDAY...Northwest wind 5 to 10 knots becoming southwest in
the afternoon. Sunny. Waves 1 to 2 feet.
.THURSDAY NIGHT...South wind 5 knots. Mostly clear. Waves 1 foot
or less.
.FRIDAY...Southwest wind 5 knots becoming south late in the
afternoon. Slight chance of rain showers in the morning, then
chance of rain showers and slight chance of thunderstorms in the
afternoon. Waves 1 foot or less.
$$
LSZ121-170415-
Chequamegon Bay-Bayfield to Oak Point WI-
241 PM CDT Wed Jul 16 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...
.TONIGHT...Northeast wind 10 to 15 knots with gusts to around
25 knots becoming north 5 to 10 knots late in the night. Chance
of rain showers early in the evening, then rain showers likely
late in the evening. Slight chance of rain showers after
midnight. Waves 1 to 2 feet.
.THURSDAY...North wind 5 knots becoming east in the afternoon.
Sunny. Waves 1 foot or less.
.THURSDAY NIGHT...Southeast wind 5 knots becoming southwest in
the late evening and overnight. Mostly clear. Waves 1 foot or
less.
.FRIDAY...Southwest wind 5 knots becoming southeast late in the
afternoon. Slight chance of rain showers in the morning, then
chance of rain showers and slight chance of thunderstorms in the
afternoon. Waves 1 foot or less.
$$
LSZ148-170415-
Oak Point to Saxon Harbor WI-
241 PM CDT Wed Jul 16 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...
.TONIGHT...Northeast wind 15 to 20 knots with gusts to around
25 knots becoming north 5 to 10 knots after midnight. Chance of
rain showers early in the evening, then rain showers likely late
in the evening. Chance of rain showers after midnight. Waves 4 to
6 feet subsiding to 1 to 2 feet. Waves occasionally to 7 feet.
.THURSDAY...North wind 5 to 10 knots becoming east late in the
afternoon. Sunny. Waves 1 to 2 feet.
.THURSDAY NIGHT...South wind 5 knots becoming southwest after
midnight. Mostly clear. Waves 1 foot or less.
.FRIDAY...Southwest wind 5 knots becoming southeast late in the
afternoon. Slight chance of rain showers in the morning, then
chance of rain showers and slight chance of thunderstorms in the
afternoon. Waves 1 foot or less.
$$
Graphical marine forecasts are available online at:
weather.gov/greatlakes
Rothstein
Open Waters Forecast
388
FZUS63 KMQT 162002
GLFLS
Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
402 PM EDT Wed Jul 16 2025
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...
This evening through Thursday morning, a 29.7 inch low over
Wisconsin will move across Lakes Michigan and Huron. By Thursday
afternoon, a 30.1 inch high moves from the Northern Plains to Lake
Superior. This high expands over the Upper Great Lakes by Friday
morning, shifting east to New England by Saturday morning. Another
30.1 inch high slowly builds over the Upper Great Lakes by Sunday
afternoon, remaining over the Great Lakes region through Monday as
it builds to 30.2 inches.
LSZ162-170800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
402 PM EDT Wed Jul 16 2025 /302 PM CDT Wed Jul 16 2025/
.LATE THIS AFTERNOON...Northeast winds 15 to 25 knots. A chance
of showers. Waves 3 to 6 feet occasionally to 8 feet.
.TONIGHT...Northeast winds 10 to 20 knots becoming north 5 to
15 knots after midnight, then increasing to 10 to 20 knots late.
A chance of showers through midnight. Waves subsiding to calm to
2 feet.
.THURSDAY...North winds 5 to 15 knots backing southwest in the
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.FRIDAY...Southwest winds 5 to 15 knots. A chance of showers. A
slight chance of thunderstorms by mid afternoon. Waves calm to
2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots backing northeast
after midnight. A chance of showers. Waves calm to 2 feet.
.SATURDAY...Northeast winds 5 to 15 knots veering south by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...East winds 10 to 20 knots diminishing to 5 to 15 knots.
A chance of showers. Waves calm to 2 feet.
$$
LSZ263-170800-
Lake Superior from Saxon Harbor WI to Upper Entrance to Portage
Canal MI 5NM off shore to the US/Canadian border including Isle
Royale National Park-
402 PM EDT Wed Jul 16 2025
.LATE THIS AFTERNOON...Northeast winds 15 to 25 knots. A chance
of showers. Waves 3 to 6 feet occasionally to 8 feet.
.TONIGHT...Northeast winds 10 to 20 knots becoming north 5 to
15 knots after midnight. A chance of showers. Waves subsiding to
calm to 2 feet.
.THURSDAY...North winds 5 to 15 knots backing southwest in the
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots. Waves building
to 1 to 3 feet, then subsiding to calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots. A slight chance of
showers by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southwest winds 5 to 15 knots backing east after
midnight. A chance of showers. Waves calm to 2 feet.
.SATURDAY...Northeast winds 5 to 15 knots veering southwest by
mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots diminishing to less
than 10 knots after midnight. Waves calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots veering southeast. Waves calm
to 2 feet.
.MONDAY...East winds 5 to 15 knots veering south. A chance of
showers. Waves calm to 2 feet.
$$
LSZ264-170800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
402 PM EDT Wed Jul 16 2025
.LATE THIS AFTERNOON...Northeast winds 10 to 20 knots. A chance
of showers. Waves 2 to 4 feet subsiding to 1 to 3 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing north after
midnight. A chance of showers. Waves 1 to 3 feet.
.THURSDAY...North winds 5 to 15 knots backing west in the
afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots. Waves building
to 1 to 3 feet, then subsiding to calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...Southwest winds 5 to 15 knots. A chance of
showers. Waves calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots diminishing to less
than 10 knots after midnight. Waves calm to 2 feet.
.SUNDAY...South winds 5 to 15 knots backing southeast. Waves calm
to 2 feet.
.MONDAY...Southeast winds 5 to 15 knots veering south. A chance
of showers. Waves calm to 2 feet.
$$
LSZ265-170800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
402 PM EDT Wed Jul 16 2025
.LATE THIS AFTERNOON...Northeast winds 10 to 20 knots. Patchy
fog. Showers likely. Waves 2 to 4 feet.
.TONIGHT...Northeast winds 10 to 20 knots becoming north 15 to
25 knots after midnight. Patchy fog. A chance of showers through
midnight. Showers likely after midnight. Waves building to 3 to
5 feet occasionally to 7 feet.
.THURSDAY...North winds 10 to 20 knots becoming southwest 5 to
15 knots late. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...West winds 5 to 15 knots backing southwest
after midnight. Waves calm to 2 feet.
.FRIDAY...Southwest winds 10 to 20 knots backing south by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...East winds 10 to 20 knots backing northeast by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots veering southeast. Waves calm
to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots veering south. A chance
of showers. Waves calm to 2 feet.
$$
LSZ266-170800-
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-
402 PM EDT Wed Jul 16 2025
.LATE THIS AFTERNOON...Northeast winds 15 to 25 knots. A chance
of showers. Waves 3 to 5 feet occasionally to 7 feet.
.TONIGHT...Northeast winds 15 to 25 knots backing north after
midnight. Patchy fog through midnight. A chance of showers and a
slight chance of thunderstorms through midnight, then showers
likely after midnight. Waves building to 3 to 6 feet occasionally
to 8 feet.
.THURSDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then becoming northwest 5 to 15 knots
late. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...West winds 5 to 15 knots backing southwest
late. Waves building to 1 to 3 feet, then subsiding to calm to
2 feet.
.FRIDAY...Southwest winds 10 to 20 knots becoming south 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots becoming north 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 5 to 15 knots. Waves calm to
2 feet.
.SUNDAY...Northwest winds 5 to 15 knots backing southeast. Waves
calm to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots veering south. A chance
of showers. Waves calm to 2 feet.
$$
LSZ267-170800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
402 PM EDT Wed Jul 16 2025
.LATE THIS AFTERNOON...Northeast winds 15 to 25 knots. A chance
of showers and a slight chance of thunderstorms. Waves 3 to
5 feet occasionally to 7 feet.
.TONIGHT...Northeast winds 15 to 25 knots backing north late. A
chance of showers through midnight. A slight chance of
thunderstorms. Showers likely after midnight. Waves building to
3 to 6 feet occasionally to 8 feet.
.THURSDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then backing northwest late. A slight
chance of showers through early afternoon. Waves subsiding to
1 to 3 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots diminishing to 5 to
15 knots after midnight, then backing southwest late. Waves
subsiding to calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...Southeast winds 5 to 15 knots becoming north 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. Waves calm to 2 feet.
.SUNDAY...Northwest winds 5 to 15 knots backing southeast. Waves
calm to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
$$
LSZ261-170200-
MAFOR 1621/
Superior West 11130 11120 13810 11800 11600 11500. A chance of
showers this evening. Waves 3 to 5 feet subsiding to 1 to 3 feet
tonight. Waves 1 to 2 feet Thursday.
Superior North Central 11120 12110 13810 11600 11610. A chance of
showers early this evening. A chance of showers overnight. Waves
2 to 4 feet subsiding to 1 to 3 feet tonight. Waves 1 to 3 feet
Thursday.
Superior South Central 13120 11826 12820 11810 11710. Waves 2 to
4 feet building to 3 to 5 feet tonight. Waves 2 to 4 feet
subsiding to 1 to 3 feet Thursday.
Superior East 14130 11836 11830 11820 11710. Waves 3 to 5 feet
tonight. Waves 3 to 5 feet subsiding to 2 to 4 feet Thursday.
$$
WFO MQT
Experimental modernized open lake forecast is available online at
weather.gov/mqt/glftable
Graphical marine forecasts are available online at:
weather.gov/greatlakes
Other Information
Great Lakes Water Levels and Forecasts - Provided by USACE
GLERL - NOAA Great Lakes Forecast System