749
FZUS52 KKEY 270812
CWFKEY

Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
412 AM EDT Sun Sep 27 2026

Florida Bay, Hawk Channel and Straits of Florida from Ocean Reef
to south of Dry Tortugas, and the extreme southeastern Gulf of
America, including The Florida Keys National Marine Sanctuary

Seas are given as significant wave height, which is the average
height of the highest 1/3 of the waves. Individual waves may be
more than twice the significant wave height.

The Wave Detail section highlights the period and direction of
origin for the highest-energy waves, as well as any long-period
swells moving in a different direction than the wind.

GMZ005-272015-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
412 AM EDT Sun Sep 27 2026

.SYNOPSIS...
An early season cold front remains draped across the distant
Straits of Florida through at least tomorrow morning, supporting
light to gentle northerlies. A Nor`easter remains off the coast of
New Jersey which will continue to support a northeasterly swell
with large periods in the eastern marine zones through tonight,
before subsiding tomorrow. The aforementioned front will begin to
push back northward through the marine zones on Monday. Winds
will then clock back to the southeast to south for early this
week, also accompanied by increasing rain and thunder chances. In
addition, strengthening high pressure is expected to move off the
Southeast U.S. coastline around the middle to latter half of next
week, merging with the Atlantic high. This will promote
freshening east to southeast breezes, potentially become moderate
to fresh.

The Approximate Shoreward Edge of the Gulf Stream as of
September 25, 2026...

43 NM south of Dry Tortugas Light, on Loggerhead Key
20 NM south of Cosgrove Shoal Light, off the Marquesas Keys
14 NM south of Sand Key Light, off Key West
 7 NM south-southeast of Looe Key, off Big Pine Key
 4 NM south-southeast of Sombrero Key Light, off Marathon
 4 NM south-southeast of Alligator Reef Light, off Islamorada
 0 NM southeast of Molasses Reef Light, off Key Largo
 1 NM west-northwest of Carysfort Reef Light, off Ocean Reef

Gulf Stream Information Courtesy of the Naval Oceanographic Office.

$$

GMZ031-272015-
Florida Bay including Barnes Sound, Blackwater Sound, and
Buttonwood Sound-
412 AM EDT Sun Sep 27 2026

.TODAY...North winds near 5 knots, becoming light and variable.
Bay waters smooth. A slight chance of showers.
.TONIGHT...West to northwest winds near 5 knots. Bay waters
smooth.
.MONDAY...Variable winds near 5 knots, becoming southwest to west.
Bay waters smooth. A slight chance of showers and thunderstorms.
.MONDAY NIGHT...Southwest winds near 5 knots, becoming light and
variable. Bay waters smooth. A chance of showers and
thunderstorms.
.TUESDAY...Variable winds near 5 knots, becoming southeast. Bay
waters smooth. Showers likely with a chance of thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Bay
waters smooth to a light chop. Showers likely with a chance of
thunderstorms.
.WEDNESDAY...East winds near 10 knots, increasing to 10 to 15
knots. Bay waters a light chop, becoming a light to moderate chop.
Showers likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds 10 to 15 knots. Bay waters a light
to moderate chop. A chance of thunderstorms. Showers likely.
.THURSDAY...East winds 10 to 15 knots, increasing 15 to 20. Bay
waters a light to moderate chop, becoming choppy. A chance of
thunderstorms. Showers likely.
.THURSDAY NIGHT...East winds 15 to 20 knots, decreasing to 10 to
15 knots. Bay waters choppy, becoming a light to moderate chop. A
chance of showers and thunderstorms.

$$

GMZ032-035-272015-
Bayside and Gulfside from Craig Key to west end of Seven Mile
Bridge-
Gulf of America from west end of Seven Mile Bridge to Halfmoon
Shoal out to 5 Fathoms-
412 AM EDT Sun Sep 27 2026

.TODAY...Northwest to north winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth.
.TONIGHT...West to northwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth.
.MONDAY...Variable winds near 5 knots, becoming southwest to south.
Seas 1 foot or less. Nearshore waters smooth. A slight chance of
showers and thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots, becoming
variable. Seas 1 foot or less. Nearshore waters smooth. Showers
likely with a chance of thunderstorms.
.TUESDAY...Variable winds near 5 knots, becoming east to
southeast. Seas 1 foot or less. Nearshore waters smooth. Showers
likely with a chance of thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
1 foot or less. Nearshore waters smooth to a light chop. Showers
likely with a chance of thunderstorms.
.WEDNESDAY...East to southeast winds near 10 knots, increasing to
10 to 15 knots. Seas 1 foot or less, building to around 1 foot.
Nearshore waters a light chop, becoming a light to moderate chop.
Showers likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds near 15 knots. Seas 1 to 2 feet.
Nearshore waters a moderate chop. Showers likely with a chance of
thunderstorms.
.THURSDAY...East winds 15 to 20 knots. Seas 1 to 2 feet, except
around 3 feet west of the Marquesas Keys. Nearshore waters
choppy. Showers likely with a chance of thunderstorms.
.THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas
1 to 2 feet, except around 3 feet west of the Marquesas Keys.
Nearshore waters choppy. Showers likely with a chance of
thunderstorms.

$$

GMZ042-272015-
Hawk Channel from Ocean Reef to Craig Key out to the reef-
412 AM EDT Sun Sep 27 2026

.TODAY...Northwest to north winds near 5 knots, becoming
southwest. Seas 1 to 2 feet. Nearshore waters smooth. A slight
chance of showers.
.TONIGHT...West winds near 5 knots. Seas 1 to 2 feet, subsiding to around
1 foot. Nearshore waters smooth.
.MONDAY...Southwest to west winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. A slight chance of showers and
thunderstorms.
.MONDAY NIGHT...Southwest to west winds near 5 knots. Seas 1 foot
or less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.TUESDAY...Variable near 5 knots, becoming east. Seas 1 foot or
less. Nearshore waters smooth. Showers likely with a chance of
thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot. Nearshore waters smooth to a light chop. Showers
likely with a chance of thunderstorms.
.WEDNESDAY...East winds near 10 knots, increasing to 10 to 15
knots. Seas around 1 foot, building to 1 to 2 feet. Nearshore
waters a light chop, becoming a light to moderate chop. Showers
likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds near 15 knots. Seas 1 to 2 feet,
building 2 to 3 feet. Nearshore waters a moderate chop. A chance
of thunderstorms. Showers.
.THURSDAY...East winds 15 to 20 knots. Seas 3 to 4 feet,
occasionally to 5 feet. Nearshore waters choppy. A chance of
thunderstorms. Showers likely.
.THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas
3 to 4 feet, occasionally to 5 feet. Nearshore waters choppy.
Showers likely with a chance of thunderstorms.

$$

GMZ043-044-272015-
Hawk Channel from Craig Key to west end of Seven Mile Bridge out
to the reef-
Hawk Channel from west end of Seven Mile Bridge to Halfmoon Shoal
out to the reef-
412 AM EDT Sun Sep 27 2026

.TODAY...Northwest winds near 5 knots. Seas around 1 foot.
Nearshore waters smooth.
.TONIGHT...West to northwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth.
.MONDAY...Variable winds near 5 knots, becoming south to
southwest. Seas 1 foot or less. Nearshore waters smooth. A chance
of showers with a slight chance of thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Seas
1 foot or less. Nearshore waters smooth. Showers likely with a
chance of thunderstorms.
.TUESDAY...Variable winds near 5 knots, becoming east to
southeast. Seas 1 foot or less. Nearshore waters smooth. Showers
likely with a chance of thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots, increasing
to near 10 knots. Seas 1 foot or less, building to around 1 foot.
Nearshore waters smooth to a light chop, becoming a light chop.
Showers likely with a chance of thunderstorms.
.WEDNESDAY...East to southeast winds near 10 knots, increasing to
10 to 15 knots. Seas around 1 foot, building to 1 to 2 feet.
Nearshore waters a light chop, becoming a light to moderate chop.
Showers likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds 15 to 20 knots. Seas 1 to 3 feet,
building 2 to 4 feet, occasionally to 5 feet. Nearshore waters
choppy. A chance of showers and thunderstorms.
.THURSDAY...East to southeast winds 15 to 20 knots. Seas 3 to
4 feet, occasionally to 5 feet. Nearshore waters choppy. A chance
of showers and thunderstorms.
.THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas
3 to 4 feet, occasionally to 5 feet. Nearshore waters choppy.
Showers likely with a chance of thunderstorms.

$$

GMZ052-072-272015-
Straits of Florida from Ocean Reef to Craig Key out 20 NM-
Straits of Florida from Ocean Reef to Craig Key 20 to 60 NM out-
412 AM EDT Sun Sep 27 2026

.TODAY...West to northwest winds near 5 knots. Seas 2 to 3 feet.
Wave Detail: North to northeast 2 feet at 13 seconds. A slight
chance of showers.
.TONIGHT...West winds near 5 knots. Seas 1 to 2 feet. Wave
Detail: North to northeast 2 feet at 13 seconds. A slight chance
of showers.
.MONDAY...Southwest to west winds near 5 knots. Seas 1 to 2 feet.
Wave Detail: North to northeast 1 foot at 12 seconds. A slight
chance of showers and thunderstorms.
.MONDAY NIGHT...South to southwest winds near 5 knots, becoming
variable. Seas 1 to 2 feet, subsiding to around 1 foot. Showers
likely with a chance of thunderstorms.
.TUESDAY...Variable near 5 knots, becoming southeast to east and
increasing to 5 to 10 knots. Seas around 1 foot. Showers likely
with a chance of thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot, building 1 to 2 feet. Showers likely with a chance
of thunderstorms.
.WEDNESDAY...East winds 10 to 15 knots. Seas 1 to 2 feet, building
2 to 3 feet. Showers likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds near 15 knots, increasing to 15 to
20 knots. Seas 3 to 4 feet, building to 4 to 5 feet, occasionally
to 6 feet. Showers with a chance of thunderstorms.
.THURSDAY...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet. Showers likely with a chance of
thunderstorms.
.THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas
around 4 feet, occasionally to 5 feet. Showers likely with a
chance of thunderstorms.

$$

GMZ053>055-073>075-272015-
Straits of Florida from Craig Key to west end of Seven Mile
Bridge out 20 NM-
Straits of Florida from west end of Seven Mile Bridge to south of
Halfmoon Shoal out 20 NM-
Straits of Florida from Halfmoon Shoal to 20 NM west of Dry
Tortugas out 20 NM-
Straits of Florida from Craig Key to west end of Seven Mile
Bridge 20 to 60 NM out-
Straits of Florida from west end of Seven Mile Bridge to south of
Halfmoon Shoal 20 to 60 NM out-
Straits of Florida from Halfmoon Shoal to 20 NM west of Dry
Tortugas 20 to 60 NM out-
412 AM EDT Sun Sep 27 2026

.TODAY...Northwest winds near 5 knots. Seas 1 to 2 feet, subsiding
to around 1 foot. Wave Detail: Northwest to north 1 foot at 5
seconds and northeast to east 1 foot at 5 seconds. A slight chance
of showers.
.TONIGHT...Variable winds near 5 knots. Seas around 1 foot. Wave
Detail: Northeast to east 1 foot at 4 seconds and northwest to
north 1 foot at 4 seconds. A slight chance of showers.
.MONDAY...Variable winds near 5 knots, becoming south to
southeast. Seas around 1 foot. Wave Detail: North to northeast 1
foot at 4 seconds. A chance of showers with a slight chance of
thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Seas
around 1 foot. Showers likely with a chance of thunderstorms.
.TUESDAY...Variable near 5 knots, becoming east to southeast and
increasing to 5 to 10 knots. Seas around 1 foot. Showers likely
with a chance of thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots, increasing
to near 10 knots. Seas around 1 foot, building to 1 to 2 feet.
Showers likely with a chance of thunderstorms.
.WEDNESDAY...East to southeast winds near 10 knots, becoming east
and increasing to 10 to 15 knots. Seas 1 to 2 feet, building 2 to
3 feet. Showers likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds near 15 knots, increasing to 15 to
20 knots. Seas 3 to 4 feet, building 4 to 5 feet, occasionally to
6 feet. Showers with a chance of thunderstorms.
.THURSDAY...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet. Showers with a chance of thunderstorms.
.THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas
4 to 5 feet, occasionally to 6 feet. Showers likely with a chance
of thunderstorms.

$$

GMZ033-034-272015-
Gulf of America from East Cape Sable to Chokoloskee 20 to 60 NM
out and beyond 5 fathoms-
Gulf of America including Dry Tortugas and Rebecca Shoal Channel-
412 AM EDT Sun Sep 27 2026

.TODAY...North to northwest winds near 5 knots. Seas around 1
foot. Wave Detail: Northwest to north 1 foot at 4 seconds.
.TONIGHT...Variable winds near 5 knots. Seas around 1 foot. Wave
Detail: Northwest to north 1 foot at 4 seconds.
.MONDAY...Variable winds near 5 knots, becoming south. Seas 1
foot or less. Wave Detail: Northwest to north 1 foot at 4
seconds. A slight chance of showers and thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Seas
1 foot or less. Showers likely with a chance of thunderstorms.
.TUESDAY...Southeast winds near 5 knots, increasing to 5 to 10
knots. Seas 1 foot or less, building to around 1 foot. Showers
likely with a chance of thunderstorms.
.TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot. Showers likely with a chance of thunderstorms.
.WEDNESDAY...East to southeast winds near 10 knots, increasing to
10 to 15 knots. Seas around 1 foot, building to 1 to 2 feet.
Showers likely with a chance of thunderstorms.
.WEDNESDAY NIGHT...East winds near 15 knots, increasing 15 to 20
knots. Seas 2 to 3 feet. Showers with a chance of thunderstorms.
.THURSDAY...East to southeast winds 15 to 20 knots. Seas 3 to
4 feet, occasionally to 5 feet. Showers with a chance of
thunderstorms.
.THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas
3 to 4 feet, occasionally to 5 feet. Showers likely with a chance
of thunderstorms.

$$