509
FZUS53 KDLH 171501
NSHDLH

Nearshore Marine Forecast
National Weather Service Duluth MN
1001 AM CDT Sun Aug 17 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.

LSZ140-141-172215-
Grand Portage to Grand Marais MN-
Grand Marais to Taconite Harbor MN-
1001 AM CDT Sun Aug 17 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...East wind 15 to 20 knots with gusts to around
30 knots. Mostly sunny. Waves 4 to 6 feet. Waves occasionally to
7 feet.
.TONIGHT...East wind 15 to 20 knots. Gusts up to 30 knots
decreasing to 25 knots after midnight. Slight chance of rain
showers in the evening, then rain showers likely and slight
chance of thunderstorms after midnight. Waves 4 to 6 feet. Waves
occasionally to 8 feet.
.MONDAY...East wind 15 to 20 knots. Gusts up to 25 knots in the
afternoon. Rain showers likely and chance of thunderstorms. Waves
3 to 5 feet. A small craft advisory may be needed.
.MONDAY NIGHT...Northeast wind 10 to 15 knots with gusts to
around 20 knots. Slight chance of thunderstorms in the evening.
Chance of rain showers through the night. Waves 2 to 4 feet.

$$

LSZ142-143-172215-
Taconite Harbor to Silver Bay Harbor MN-
Silver Bay Harbor to Two Harbors MN-
1001 AM CDT Sun Aug 17 2025

...GALE WARNING IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...East wind 20 to 25 knots. Gusts up to 30 knots
increasing to 35 knots late. Partly sunny. Waves 4 to 7 feet.
Waves occasionally to 9 feet.
.TONIGHT...East wind 15 to 20 knots. Gusts up to 35 knots
decreasing to 20 knots. Chance of rain showers and slight chance
of thunderstorms in the evening, then rain showers likely and
chance of thunderstorms after midnight. Waves 4 to 7 feet. Waves
occasionally to 10 feet.
.MONDAY...East wind 10 to 15 knots with gusts to around 20 knots.
Rain showers likely and chance of thunderstorms in the morning,
then chance of rain showers and slight chance of thunderstorms in
the afternoon. Waves 2 to 4 feet subsiding to 1 to 3 feet late in
the afternoon. A small craft advisory may be needed.
.MONDAY NIGHT...Northeast wind 5 to 10 knots. Chance of showers
and slight chance of thunderstorms in the evening. Waves 1 to
3 feet.

$$

LSZ144-145-172215-
Two Harbors to Duluth MN-Duluth MN to Port Wing WI-
1001 AM CDT Sun Aug 17 2025

...GALE WARNING IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...Northeast wind 20 to 25 knots with gales to
around 35 knots. Partly sunny. Waves 4 to 7 feet. Waves
occasionally to 9 feet.
.TONIGHT...East wind 15 to 20 knots. Gusts up to 35 knots
decreasing to 20 knots. Chance of showers in the evening. Chance
of thunderstorms through the night. Showers after midnight. Waves
4 to 7 feet subsiding to 3 to 5 feet early in the morning. Waves
occasionally to 10 feet.
.MONDAY...East wind 10 to 15 knots becoming northeast 5 to
10 knots late in the afternoon. Showers likely and chance of
thunderstorms in the morning, then chance of showers and slight
chance of thunderstorms in the afternoon. Waves 1 to 3 feet
subsiding to 1 to 2 feet in the late morning and afternoon.
.MONDAY NIGHT...Northeast wind 5 to 10 knots. Chance of showers
and slight chance of thunderstorms in the evening. Waves 1 to
2 feet.

$$

LSZ146-172215-
Port Wing to Sand Island WI-
1001 AM CDT Sun Aug 17 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...East wind 15 to 20 knots with gusts to around
30 knots. Mostly sunny. Waves 4 to 7 feet. Waves occasionally to
9 feet.
.TONIGHT...East wind 15 to 20 knots. Gusts up to 30 knots
decreasing to 20 knots. Chance of showers in the evening. Chance
of thunderstorms through the night. Showers after midnight. Waves
4 to 7 feet subsiding to 2 to 4 feet early in the morning. Waves
occasionally to 9 feet.
.MONDAY...East wind 5 to 10 knots becoming northeast late in the
afternoon. Chance of thunderstorms in the morning. Showers likely
through the day. Slight chance of thunderstorms in the afternoon.
Waves 1 to 2 feet.
.MONDAY NIGHT...Northeast wind 5 to 10 knots. Chance of showers
and slight chance of thunderstorms in the evening. Waves 1 to
2 feet.

$$

LSZ147-172215-
Sand Island to Bayfield WI-
1001 AM CDT Sun Aug 17 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...East wind 15 to 20 knots with gusts to around
30 knots. Mostly sunny. Waves 4 to 7 feet. Waves occasionally to
9 feet.
.TONIGHT...East wind 15 to 20 knots with gusts to around 30 knots
becoming southeast 10 to 15 knots with gusts to around 20 knots
early in the morning. Chance of showers and slight chance of
thunderstorms in the evening, then showers and chance of
thunderstorms after midnight. Waves 4 to 7 feet. Waves
occasionally to 9 feet.
.MONDAY...East wind 5 to 10 knots. Gusts up to 20 knots early in
the morning. Showers likely and chance of thunderstorms. Waves
1 to 2 feet.
.MONDAY NIGHT...Northeast wind 5 to 10 knots. Gusts up to
20 knots early in the morning. Slight chance of thunderstorms in
the evening. Chance of showers through the night. Waves 1 to
2 feet.

$$

LSZ150-172215-
Outer Apostle Islands Beyond 5 NM from Mainland-
1001 AM CDT Sun Aug 17 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...Northeast wind 15 to 20 knots with gusts to
around 30 knots. Mostly sunny. Waves 4 to 7 feet. Waves
occasionally to 9 feet.
.TONIGHT...East wind 15 to 20 knots with gusts to around 30 knots
becoming southeast 10 to 15 knots with gusts to around 20 knots
early in the morning. Slight chance of showers and thunderstorms
in the evening, then showers and chance of thunderstorms after
midnight. Waves 5 to 8 feet subsiding to 3 to 5 feet early in the
morning. Waves occasionally to 10 feet.
.MONDAY...East wind 10 to 15 knots. Gusts up to 20 knots in the
morning. Showers likely in the morning. Chance of thunderstorms
through the day. Chance of showers in the afternoon. Waves 1 to
3 feet subsiding to 1 to 2 feet in the late morning and
afternoon.
.MONDAY NIGHT...Northeast wind 5 to 10 knots with gusts to around
20 knots rising to 10 to 15 knots with gusts to around 20 knots
early in the morning. Slight chance of thunderstorms in the
evening. Chance of showers through the night. Waves 1 to 3 feet.

$$

LSZ121-172215-
Chequamegon Bay-Bayfield to Oak Point WI-
1001 AM CDT Sun Aug 17 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...Northeast wind 15 to 20 knots. Gusts up to
25 knots increasing to 30 knots late. Mostly sunny. Waves 2 to
4 feet.
.TONIGHT...Northeast wind 15 to 20 knots with gusts to around
30 knots becoming east 5 to 10 knots after midnight. Chance of
showers in the evening. Chance of thunderstorms through the
night. Showers likely after midnight. Waves 2 to 4 feet subsiding
to 1 to 3 feet after midnight.
.MONDAY...Southeast wind 5 to 10 knots. Showers likely and chance
of thunderstorms. Waves 1 to 2 feet.
.MONDAY NIGHT...Northeast wind 5 to 10 knots becoming north after
midnight. Slight chance of thunderstorms in the evening. Chance
of showers through the night. Waves 1 foot or less.

$$

LSZ148-172215-
Oak Point to Saxon Harbor WI-
1001 AM CDT Sun Aug 17 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM CDT THIS EVENING...

.REST OF TODAY...Northeast wind 15 to 20 knots. Gusts up to
25 knots increasing to 30 knots late. Mostly sunny. Waves 4 to
7 feet. Waves occasionally to 9 feet.
.TONIGHT...East wind 15 to 20 knots with gusts to around 30 knots
becoming southeast 10 to 15 knots with gusts to around 20 knots
after midnight. Chance of showers in the evening. Chance of
thunderstorms through the night. Showers likely after midnight.
Waves 4 to 7 feet subsiding to 1 to 3 feet. Waves occasionally to
9 feet.
.MONDAY...Southeast wind 5 to 10 knots. Showers likely and chance
of thunderstorms. Waves 1 to 2 feet.
.MONDAY NIGHT...Northeast wind 5 to 10 knots becoming north after
midnight. Chance of thunderstorms in the evening. Chance of
showers through the night. Waves 1 to 2 feet.

$$

Graphical marine forecasts are available online at:
weather.gov/greatlakes

LE