163
FZUS52 KKEY 110820
CWFKEY

Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
420 AM EDT Mon Aug 11 2025

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.

Wave Detail will include details about the period and direction
of origin for the highest energy waves. Long-period swells coming
from a different direction than the wind would be included in the
Wave Detail.

GMZ005-112030-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
420 AM EDT Mon Aug 11 2025

.SYNOPSIS...An Atlantic Ridge will build westward and across the
Keys starting today. This will result in gentle to moderate east
to southeast breezes over the next couple of days. The ridge will
buckle briefly mid week, allowing for breezes to slacken
temporarily. Breezes freshen to gentle to moderate once again
towards the end of the week.

The Approximate Shoreward Edge of the Gulf Stream as of August 8...

84 NM South of Dry Tortugas Light...on Loggerhead Key.
53 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
41 NM South of Sand Key Light...off Key West.
18 NM South of Looe Key...off Big Pine Key.
 9 NM Southeast of Sombrero Key Light...off Marathon.
 7 NM Southeast of Alligator Reef Light...off Islamorada.
 3 NM Southeast of Molasses Reef Light...off Key Largo.
 3 NM Southeast of Carysfort Reef Light...off Ocean Reef.

Gulf Stream Information Courtesy of the National Weather Service in
Key West based on products from NASA SPoRT.

$$

GMZ031-112030-
Florida Bay including Barnes Sound, Blackwater Sound, and
Buttonwood Sound-
420 AM EDT Mon Aug 11 2025

.TODAY...East to southeast winds 5 to 10 knots early, increasing
to 10 to 15 knots. Bay waters smooth to a light chop, becoming a
light to moderate chop. Scattered showers and isolated
thunderstorms.
.TONIGHT...East to southeast winds 10 to 15 knots. Bay waters a
light to moderate chop. Scattered showers and isolated
thunderstorms.
.TUESDAY...East to southeast winds 10 to 15 knots, decreasing to
near 10 knots in the afternoon. Bay waters a light to moderate
chop, becoming a light chop. Scattered showers and isolated
thunderstorms.
.TUESDAY NIGHT...East to southeast winds near 10 knots. Bay
waters a light chop. Scattered showers and isolated
thunderstorms.
.WEDNESDAY...East to southeast winds 5 to 10 knots. Bay waters
smooth to a light chop. Scattered showers and isolated
thunderstorms.
.WEDNESDAY NIGHT...East winds 5 to 10 knots. Bay waters smooth to
a light chop. Scattered showers and isolated thunderstorms.
.THURSDAY...East winds 5 to 10 knots. Bay waters smooth to a
light chop. Scattered showers and isolated thunderstorms.
.THURSDAY NIGHT...East winds increasing to near 10 knots. Bay
waters becoming a light chop. Isolated showers and thunderstorms.
.FRIDAY...East winds near 10 knots. Bay waters a light chop.
Scattered showers and isolated thunderstorms.
.FRIDAY NIGHT...Northeast to east winds near 10 knots. Bay waters
a light chop. Isolated showers and thunderstorms.

$$

GMZ032-035-112030-
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-
420 AM EDT Mon Aug 11 2025

.TODAY...East to southeast winds 5 to 10 knots early, increasing
to 10 to 15 knots. Seas around 1 foot, except building to 1 to 2
feet west of the Marquesas Keys. Nearshore waters smooth to a
light chop, becoming a light to moderate chop. Scattered showers
and isolated thunderstorms.
.TONIGHT...East to southeast winds 10 to 15 knots. Seas around 1
foot, except 1 to 2 feet west of the Marquesas Keys. Nearshore
waters a light to moderate chop. Scattered showers and isolated
thunderstorms.
.TUESDAY...East to southeast winds 10 to 15 knots, decreasing to
near 10 knots in the afternoon. Seas around 1 foot, except 1 to 2
feet west of the Marquesas Keys. Nearshore waters a light to
moderate chop, becoming a light chop. Scattered showers and
isolated thunderstorms.
.TUESDAY NIGHT...East to southeast winds near 10 knots. Seas
around 1 foot. Nearshore waters a light chop. Scattered showers
and isolated thunderstorms.
.WEDNESDAY...East to southeast winds 5 to 10 knots. Seas 1 foot
or less. Nearshore waters smooth to a light chop. Scattered
showers and isolated thunderstorms.
.WEDNESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
1 foot or less. Nearshore waters smooth to a light chop.
Scattered showers and isolated thunderstorms.
.THURSDAY...East to southeast winds 5 to 10 knots. Seas 1 foot or
less. Nearshore waters smooth to a light chop. Scattered showers
and isolated thunderstorms.
.THURSDAY NIGHT...East winds increasing to near 10 knots. Seas
building to around 1 foot. Nearshore waters becoming a light
chop. Isolated showers and thunderstorms.
.FRIDAY...East winds near 10 knots. Seas around 1 foot. Nearshore
waters a light chop. Scattered showers and isolated
thunderstorms.
.FRIDAY NIGHT...Northeast to east winds near 10 knots. Seas around
1 foot. Nearshore waters a light chop. Isolated showers and
thunderstorms.

$$

GMZ042>044-112030-
Hawk Channel from Ocean Reef to Craig Key out to the reef-
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-
420 AM EDT Mon Aug 11 2025

.TODAY...East to southeast winds 5 to 10 knots early, increasing
to 10 to 15 knots. Seas 1 to 2 feet, building to around 2 feet.
Nearshore waters smooth to a light chop, becoming a light to
moderate chop. Scattered showers and isolated thunderstorms.
.TONIGHT...East to southeast winds 10 to 15 knots. Seas around 2
feet. Nearshore waters a light to moderate chop. Scattered showers
and isolated thunderstorms.
.TUESDAY...East to southeast winds 10 to 15 knots. Seas around 2
feet, subsiding to 1 to 2 feet. Nearshore waters a light to
moderate chop. Scattered showers and isolated thunderstorms.
.TUESDAY NIGHT...East to southeast winds near 10 knots. Seas 1 to
2 feet, subsiding to around 1 foot. Nearshore waters a light
chop. Scattered showers and isolated thunderstorms.
.WEDNESDAY...East to southeast winds decreasing to 5 to 10 knots.
Seas around 1 foot. Nearshore waters becoming smooth to a light
chop. Isolated showers and thunderstorms.
.WEDNESDAY NIGHT...East winds near 10 knots. Seas around 1 foot.
Nearshore waters a light chop. Scattered showers and isolated
thunderstorms.
.THURSDAY...East winds 5 to 10 knots. Seas around 1 foot.
Nearshore waters smooth to a light chop. Scattered showers and
isolated thunderstorms.
.THURSDAY NIGHT...East winds near 10 knots. Seas around 1 foot.
Nearshore waters a light chop. Isolated showers and
thunderstorms.
.FRIDAY...East winds near 10 knots. Seas building to 1 to 2 feet.
Nearshore waters a light chop. Scattered showers and isolated
thunderstorms.
.FRIDAY NIGHT...Northeast to east winds near 10 knots. Seas
1 to 2 feet. Nearshore waters a light chop. Isolated showers and
thunderstorms.

$$

GMZ052>055-072>075-112030-
Straits of Florida from Ocean Reef to Craig Key out 20 NM-
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 Ocean Reef to Craig Key 20 to 60 NM out-
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-
420 AM EDT Mon Aug 11 2025

.TODAY...East to southeast winds 5 to 10 knots early, increasing
to 10 to 15 knots. Seas 1 to 2 feet, building to 2 to 3 feet. Wave
Detail: East to southeast 2 feet at 4 seconds. Scattered showers
and isolated thunderstorms.
.TONIGHT...East to southeast winds 10 to 15 knots. Seas 2 to
3 feet. Wave Detail: East 2 feet at 4 seconds. Scattered showers
and isolated thunderstorms.
.TUESDAY...Southeast winds 10 to 15 knots, becoming east to
southeast near 10 knots in the afternoon. Seas 2 to 3 feet,
subsiding to around 2 feet. Wave Detail: East to southeast 2 feet
at 4 seconds. Scattered showers and isolated thunderstorms.
.TUESDAY NIGHT...East winds near 10 knots. Seas 1 to 2 feet.
Scattered showers and isolated thunderstorms.
.WEDNESDAY...East to southeast winds decreasing to 5 to 10 knots.
Seas 1 to 2 feet. Isolated showers and thunderstorms.
.WEDNESDAY NIGHT...East winds near 10 knots. Seas 1 to 2 feet.
Isolated showers and thunderstorms.
.THURSDAY...East winds 5 to 10 knots. Seas 1 to 2 feet. Scattered
showers and isolated thunderstorms.
.THURSDAY NIGHT...East winds near 10 knots. Seas 1 to 2 feet.
Isolated showers and thunderstorms.
.FRIDAY...East winds near 10 knots. Seas building to around 2
feet. Scattered showers and isolated thunderstorms.
.FRIDAY NIGHT...Northeast to east winds near 10 knots. Seas
around 2 feet. Isolated showers and thunderstorms.

$$

GMZ033-034-112030-
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-
420 AM EDT Mon Aug 11 2025

.TODAY...Southeast winds 5 to 10 knots early, increasing to 10 to
15 knots. Seas around 1 foot, building to 1 to 2 feet. Wave
Detail: Southeast 2 feet at 3 seconds. Scattered showers and
isolated thunderstorms.
.TONIGHT...East to southeast winds 10 to 15 knots. Seas 1 to 2
feet, building to around 2 feet. Wave Detail: East to southeast 2
feet at 4 seconds. Scattered showers and isolated thunderstorms.
.TUESDAY...Southeast winds 10 to 15 knots, decreasing to near 10
knots in the afternoon. Seas subsiding to 1 to 2 feet. Wave
Detail: Southeast 2 feet at 4 seconds. Scattered showers and
isolated thunderstorms.
.TUESDAY NIGHT...East to southeast winds near 10 knots. Seas
around 1 foot. Scattered showers and isolated thunderstorms.
.WEDNESDAY...East to southeast winds 5 to 10 knots. Seas around
1 foot. Isolated showers and thunderstorms.
.WEDNESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot. Scattered showers and isolated thunderstorms.
.THURSDAY...East to southeast winds 5 to 10 knots, decreasing to
near 5 knots. Seas subsiding to 1 foot or less. Scattered showers
and isolated thunderstorms.
.THURSDAY NIGHT...East winds increasing to 5 to 10 knots. Seas
building to around 1 foot. Scattered showers and isolated
thunderstorms.
.FRIDAY...East to southeast winds 5 to 10 knots. Seas around 1
foot. Scattered showers and isolated thunderstorms.
.FRIDAY NIGHT...East winds 5 to 10 knots. Seas around 1 foot.
Isolated showers and thunderstorms.

$$