818
FZUS52 KKEY 161430
CWFKEY

Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
1030 AM EDT Sun Aug 16 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.

GMZ005-170230-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
1030 AM EDT Sun Aug 16 2026

.SYNOPSIS...Breezes are on track to slacken from gentle to
moderate to light to gentle across the Florida Keys coastal waters
this week. Northward movement of the subtropical ridge away from
the Keys will allow a col region to set up between Florida and
Cuba. Mariners can expect periods of light and variable breezes
this week. Shower coverage will be kept far below normal because
of a Saharan Air Layer moving over the Keys waters.

The Approximate Shoreward Edge of the Gulf Stream as of
August 13, 2026...

38 NM South of Dry Tortugas Light...on Loggerhead Key.
20 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
17 NM South of Sand Key Light...off Key West.
21 NM South of Looe Key...off Big Pine Key.
18 NM Southeast of Sombrero Key Light...off Marathon.
 7 NM Southeast of Alligator Reef Light...off Islamorada.
 7 NM Southeast of Molasses Reef Light...off Key Largo.
 2 NM Southeast of Carysfort Reef Light...off Ocean Reef.

Gulf Stream Information Courtesy of the National Weather Service in
Key West, using data from RTOFS and NASA SPoRT SST.

$$

GMZ031-170230-
Florida Bay including Barnes Sound, Blackwater Sound, and
Buttonwood Sound-
1030 AM EDT Sun Aug 16 2026

.THIS AFTERNOON...East winds near 10 knots, decreasing to 5 to 10
knots. Bay waters a light chop, becoming smooth to a light chop.
.TONIGHT...East winds 5 to 10 knots. Bay waters smooth to a light
chop.
.MONDAY...East to southeast winds near 5 knots. Bay waters
smooth.
.MONDAY NIGHT...Variable winds near 5 knots. Bay waters smooth.
.TUESDAY...Southwest to west winds near 5 knots, increasing to 5
to 10 knots. Bay waters smooth, becoming smooth to a light chop.
.TUESDAY NIGHT...West to northwest winds 5 to 10 knots. Bay
waters smooth to a light chop.
.WEDNESDAY...West winds 5 to 10 knots. Bay waters smooth to a
light chop. A slight chance of showers and thunderstorms.
.WEDNESDAY NIGHT...Southwest to west winds 5 to 10 knots. Bay
waters smooth to a light chop. A slight chance of showers.
.THURSDAY...South to southwest winds 5 to 10 knots. Bay waters smooth
to a light chop. A slight chance of showers and thunderstorms.
.THURSDAY NIGHT...South winds near 5 knots. Bay waters smooth. A
slight chance of showers.

$$

GMZ032-035-170230-
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-
1030 AM EDT Sun Aug 16 2026

.THIS AFTERNOON...East to southeast winds near 10 knots, becoming
east and decreasing to 5 to 10 knots. Seas 1 to 2 feet. Nearshore
waters a light chop, becoming smooth to a light chop.
.TONIGHT...East winds 5 to 10 knots. Seas around 1 foot.
Nearshore waters smooth to a light chop.
.MONDAY...East to southeast winds 5 to 10 knots, becoming variable
near 5 knots. Seas 1 foot or less. Nearshore waters smooth to a
light chop, becoming smooth.
.MONDAY NIGHT...Variable winds near 5 knots. Seas 1 foot or less.
Nearshore waters smooth.
.TUESDAY...Northwest to north winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth.
.TUESDAY NIGHT...Northwest winds 5 to 10 knots. Seas 1 foot or
less. Nearshore waters smooth to a light chop.
.WEDNESDAY...West to northwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. A slight chance of showers and
thunderstorms.
.WEDNESDAY NIGHT...West to northwest winds near 5 knots. Seas 1
foot or less. Nearshore waters smooth. A slight chance of showers
and thunderstorms.
.THURSDAY...South to southwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. A slight chance of showers.
.THURSDAY NIGHT...Southwest winds near 5 knots, becoming
southeast to south. Seas 1 foot or less. Nearshore waters smooth.
A slight chance of showers and thunderstorms.

$$

GMZ042>044-170230-
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-
1030 AM EDT Sun Aug 16 2026

.THIS AFTERNOON...East to southeast winds near 10 knots. Seas
around 2 feet. Nearshore waters a light chop.
.TONIGHT...East winds 5 to 10 knots. Seas 1 to 2 feet. Nearshore
waters smooth to a light chop.
.MONDAY...East to southeast winds near 5 knots, becoming variable.
Seas subsiding to around 1 foot. Nearshore waters smooth.
.MONDAY NIGHT...Variable winds near 5 knots. Seas around 1 foot.
Nearshore waters smooth.
.TUESDAY...Northwest to north winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth.
.TUESDAY NIGHT...Northwest to north winds 5 to 10 knots. Seas 1
foot or less. Nearshore waters smooth to a light chop.
.WEDNESDAY...West to northwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. A slight chance of showers and
thunderstorms.
.WEDNESDAY NIGHT...West to northwest winds 5 to 10 knots, becoming
southwest to west near 5 knots. Seas 1 foot or less. Nearshore
waters smooth to a light chop, becoming smooth. A slight chance of
showers.
.THURSDAY...South to southwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth.
.THURSDAY NIGHT...Southeast to south winds near 5 knots. Seas 1
foot or less. Nearshore waters smooth. A slight chance of showers.

$$

GMZ052>055-072>075-170230-
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-
1030 AM EDT Sun Aug 16 2026

.THIS AFTERNOON...East to southeast winds 10 to 15 knots,
decreasing to near 10 knots. Seas 2 to 3 feet. Wave Detail: East
3 feet at 5 seconds.
.TONIGHT...East winds 10 to 15 knots, decreasing to near 10 knots.
Seas 2 to 3 feet, subsiding to 1 to 2 feet. Wave Detail: East 3
feet at 5 seconds.
.MONDAY...East winds 5 to 10 knots. Seas around 2 feet. Wave
Detail: East 2 feet at 5 seconds.
.MONDAY NIGHT...East winds 5 to 10 knots. Seas 1 to 2 feet.
.TUESDAY...East winds near 5 knots, becoming variable. Seas
around 1 foot.
.TUESDAY NIGHT...Northwest to north winds 5 to 10 knots. Seas
around 1 foot.
.WEDNESDAY...West to northwest winds near 5 knots. Seas around 1
foot.
.WEDNESDAY NIGHT...West to northwest winds near 5 knots, becoming
southeast. Seas around 1 foot.
.THURSDAY...Southeast to south winds near 5 knots. Seas around 1
foot.
.THURSDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot. A slight chance of showers.

$$

GMZ033-034-170230-
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-
1030 AM EDT Sun Aug 16 2026

.THIS AFTERNOON...East to southeast winds near 10 knots,
decreasing to 5 to 10 knots. Seas 1 to 2 feet. Wave Detail: East 2
feet at 4 seconds.
.TONIGHT...East winds 5 to 10 knots. Seas 1 to 2 feet. Wave
Detail: East 1 foot at 3 seconds.
.MONDAY...Northeast to east winds 5 to 10 knots. Seas around 1
foot. Wave Detail: East 1 foot at 3 seconds.
.MONDAY NIGHT...North to northeast winds near 5 knots. Seas
1 foot or less.
.TUESDAY...Northwest to north winds near 5 knots. Seas 1 foot or
less.
.TUESDAY NIGHT...Northwest winds 5 to 10 knots. Seas around 1
foot.
.WEDNESDAY...West to northwest winds near 5 knots. Seas around
1 foot. A slight chance of showers and thunderstorms.
.WEDNESDAY NIGHT...West to northwest winds 5 to 10 knots. Seas
around 1 foot. A slight chance of showers and thunderstorms.
.THURSDAY...Southwest to west winds near 5 knots. Seas around 1
foot. A slight chance of showers.
.THURSDAY NIGHT...West to northwest winds near 5 knots, becoming
southeast to south. Seas around 1 foot. A slight chance of
showers and thunderstorms.

$$