200
FZUS52 KKEY 272024
CWFKEY

Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
424 PM EDT Wed Aug 27 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.

GMZ005-280830-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
424 PM EDT Wed Aug 27 2025

.SYNOPSIS...An early season Canadian high pressure system will
continue to traverse the eastern United States over the next few
days. As it does, it will enhance the pressure gradient slightly
across the Florida Keys marine zones. As a result, expect light to
gentle breezes this afternoon becoming gentle to moderate during
the evening, especially across the Straits of Florida. As the high
moves into the Atlantic late week and over the weekend, breezes
will shift to the east to southeast and slacken. Increased
moisture will support higher shower and thunderstorm coverage by
the end of the week and for the weekend.

The Approximate Shoreward Edge of the Gulf Stream as of August 21...

20 NM South of Dry Tortugas Light...on Loggerhead Key.
 9 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
 9 NM South of Sand Key Light...off Key West.
13 NM South of Looe Key...off Big Pine Key.
17 NM Southeast of Sombrero Key Light...off Marathon.
17 NM Southeast of Alligator Reef Light...off Islamorada.
13 NM Southeast of Molasses Reef Light...off Key Largo.
 5 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.

$$

GMZ031-280830-
Florida Bay including Barnes Sound, Blackwater Sound, and
Buttonwood Sound-
424 PM EDT Wed Aug 27 2025

.TONIGHT...East winds 5 to 10 knots. Bay waters smooth to a light
chop. Scattered showers and isolated thunderstorms.
.THURSDAY...East winds near 10 knots. Bay waters a light chop.
Scattered showers and isolated thunderstorms.
.THURSDAY NIGHT...East winds near 10 knots, becoming east to
southeast and decreasing to 5 to 10 knots. Bay waters a light
chop, becoming smooth to a light chop. Scattered showers and
isolated thunderstorms.
.FRIDAY...East to southeast winds near 5 knots. Bay waters
smooth. Scattered showers and thunderstorms.
.FRIDAY NIGHT...East to southeast winds near 5 knots, becoming
southeast to south. Bay waters smooth. Scattered showers and
thunderstorms.
.SATURDAY...Southeast to south winds near 5 knots, becoming
southwest to west. Bay waters smooth. Scattered showers and
thunderstorms.
.SATURDAY NIGHT...Variable winds near 5 knots. Bay waters smooth.
Scattered showers and thunderstorms.
.SUNDAY AND SUNDAY NIGHT...Southwest to west winds near 5 knots.
Bay waters smooth. Scattered showers and thunderstorms.
.MONDAY...Southwest to west winds near 5 knots, becoming west and
increasing to near 10 knots. Bay waters smooth, becoming a light
chop. Scattered showers and thunderstorms.
.MONDAY NIGHT...West to northwest winds 10 to 15 knots, decreasing
to 5 to 10 knots. Bay waters a light to moderate chop, becoming
smooth to a light chop. Scattered showers and thunderstorms.

$$

GMZ032-035-280830-
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-
424 PM EDT Wed Aug 27 2025

.TONIGHT...East winds 5 to 10 knots. Seas 1 foot or less.
Nearshore waters smooth to a light chop. Scattered showers and
isolated thunderstorms.
.THURSDAY...East winds near 10 knots. Seas around 1 foot.
Nearshore waters a light chop. Scattered showers and isolated
thunderstorms.
.THURSDAY NIGHT...East winds near 10 knots, becoming east to
southeast. Seas around 1 foot, except 1 to 2 feet west of the
Marquesas Keys. Nearshore waters a light chop. Scattered showers
and isolated thunderstorms.
.FRIDAY...East to southeast winds 5 to 10 knots. Seas around 1
foot, subsiding to 1 foot or less. Nearshore waters smooth to a
light chop. Scattered showers and thunderstorms.
.FRIDAY NIGHT...East to southeast winds 5 to 10 knots. Seas 1
foot or less. Nearshore waters smooth to a light chop. Scattered
showers and thunderstorms.
.SATURDAY...Southeast to south winds 5 to 10 knots, becoming
southwest to west and decreasing to near 5 knots. Seas 1 foot or
less. Nearshore waters smooth to a light chop, becoming smooth.
Scattered showers and thunderstorms.
.SATURDAY NIGHT...Variable winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. Scattered showers and
thunderstorms.
.SUNDAY...Southwest to west winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. Scattered showers and
thunderstorms.
.SUNDAY NIGHT...West to northwest winds 5 to 10 knots. Seas
around 1 foot. Nearshore waters smooth to a light chop. Scattered
showers and thunderstorms.
.MONDAY...Southwest to west winds 5 to 10 knots, becoming west.
Seas around 1 foot. Nearshore waters smooth to a light chop.
Scattered showers and thunderstorms.
.MONDAY NIGHT...West to northwest winds 10 to 15 knots, becoming
5 to 10 knots. Seas 1 to 2 feet. Nearshore waters a light to
moderate chop, becoming smooth to a light chop. Scattered showers
and thunderstorms.

$$

GMZ042>044-280830-
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-
424 PM EDT Wed Aug 27 2025

.TONIGHT...East winds near 10 knots. Seas 1 to 2 feet. Nearshore
waters a light chop. Scattered showers and isolated
thunderstorms.
.THURSDAY...East winds near 10 knots. Seas 1 to 2 feet. Nearshore
waters a light chop. Scattered showers and isolated
thunderstorms.
.THURSDAY NIGHT...East to southeast winds near 10 knots. Seas 1
to 2 feet. Nearshore waters a light chop. Scattered showers and
isolated thunderstorms.
.FRIDAY...East to southeast winds 5 to 10 knots. Seas subsiding to
around 1 foot. Nearshore waters smooth to a light chop. Scattered
showers and thunderstorms.
.FRIDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot. Nearshore waters smooth to a light chop. Scattered
showers and thunderstorms.
.SATURDAY...Southeast to south winds near 5 knots, becoming
southwest to west. Seas 1 foot or less. Nearshore waters smooth.
Scattered showers and thunderstorms.
.SATURDAY NIGHT...Variable winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. Scattered showers and
thunderstorms.
.SUNDAY...Southwest to west winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. Scattered showers and
thunderstorms.
.SUNDAY NIGHT...West winds near 5 knots. Seas 1 foot or less.
Nearshore waters smooth. Scattered showers and thunderstorms.
.MONDAY...Southwest to west winds near 5 knots, increasing to
near 10 knots. Seas around 1 foot. Nearshore waters smooth,
becoming a light chop. Scattered showers and thunderstorms.
.MONDAY NIGHT...West to northwest winds 10 to 15 knots, decreasing
to 5 to 10 knots. Seas 1 to 2 feet. Nearshore waters a light to
moderate chop, becoming smooth to a light chop. Scattered showers
and thunderstorms.

$$

GMZ052>055-072>075-280830-
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-
424 PM EDT Wed Aug 27 2025

.TONIGHT...East winds 10 to 15 knots. Seas 2 to 3 feet. Wave
Detail: East 3 feet at 4 seconds. Scattered showers and isolated
thunderstorms.
.THURSDAY...East winds near 10 knots. Seas 2 to 3 feet. Wave
Detail: East 2 feet at 5 seconds. Scattered showers and isolated
thunderstorms.
.THURSDAY NIGHT...East to southeast winds 10 to 15 knots,
decreasing to near 10 knots. Seas 2 to 3 feet. Wave Detail: East 3
feet at 4 seconds. Scattered showers and isolated thunderstorms.
.FRIDAY...East to southeast winds 5 to 10 knots. Seas subsiding to 1
to 2 feet. Scattered showers and thunderstorms.
.FRIDAY NIGHT...East to southeast winds 5 to 10 knots. Seas 1 to
2 feet. Scattered showers and thunderstorms.
.SATURDAY...Southeast to south winds near 5 knots, becoming
variable. Seas around 1 foot. Scattered showers and
thunderstorms.
.SATURDAY NIGHT...Variable winds near 5 knots. Seas around 1 foot.
Scattered showers and thunderstorms.
.SUNDAY...Southwest to west winds near 5 knots, becoming west.
Seas around 1 foot. Scattered showers and thunderstorms.
.SUNDAY NIGHT...West winds near 5 knots. Seas around 1 foot.
Scattered showers and thunderstorms.
.MONDAY...Southwest to west winds 5 to 10 knots. Seas around 1
foot. Scattered showers and thunderstorms.
.MONDAY NIGHT...West to northwest winds 5 to 10 knots. Seas 1 to
2 feet. Scattered showers and thunderstorms.

$$

GMZ033-034-280830-
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-
424 PM EDT Wed Aug 27 2025

.TONIGHT...East winds 5 to 10 knots. Seas around 1 foot. Wave
Detail: Northeast to east 1 foot at 2 seconds and northwest
1 foot at 3 seconds. Scattered showers and isolated
thunderstorms.
.THURSDAY...East winds 5 to 10 knots. Seas around 1 foot. Wave
Detail: East 1 foot at 3 seconds. Scattered showers and isolated
thunderstorms.
.THURSDAY NIGHT...East winds near 10 knots. Seas 1 to 2 feet.
Wave Detail: East 1 foot at 3 seconds. Scattered showers and
isolated thunderstorms.
.FRIDAY...East to southeast winds decreasing to 5 to 10 knots.
Seas subsiding to around 1 foot. Scattered showers and
thunderstorms.
.FRIDAY NIGHT...Northeast to east winds 5 to 10 knots, becoming
southeast after midnight. Seas around 1 foot. Scattered showers
and thunderstorms.
.SATURDAY...Southeast to south winds near 5 knots, becoming
variable. Seas 1 foot or less. Scattered showers and
thunderstorms.
.SATURDAY NIGHT...Variable winds near 5 knots. Seas 1 foot or
less. Scattered showers and thunderstorms.
.SUNDAY...Southwest to west winds near 5 knots. Seas 1 foot or
less. Scattered showers and thunderstorms.
.SUNDAY NIGHT...West to northwest winds near 5 knots. Seas 1
foot or less. Scattered showers and thunderstorms.
.MONDAY...West winds 5 to 10 knots. Seas around 1 foot. Scattered
showers and thunderstorms.
.MONDAY NIGHT...West to northwest winds near 10 knots, becoming
northwest. Seas 1 to 2 feet. Scattered showers and thunderstorms.

$$

MC/MJV