850
FZUS52 KKEY 042019
CWFKEY

Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
419 PM EDT Fri Sep 4 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.

GMZ005-050830-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
419 PM EDT Fri Sep 4 2026

.SYNOPSIS...
The western periphery of a weak North Atlantic high will remain
in loose control of the Keys coastal waters for the next few
days. Light to gentle east to southeast breezes overnight through
morning will become light and at times variable during the
afternoon and evenings. Waves of low-level moisture pushing
across the Keys will support somewhat elevated rain and thunder
chances through Sunday, possibly returning to near normal for
early next week.

The Approximate Shoreward Edge of the Gulf Stream as of September 2, 2026...

34 NM south-southwest of Dry Tortugas Light, on Loggerhead Key
34 NM south-southeast of Cosgrove Shoal Light, off the Marquesas Keys
26 NM south-southeast of Sand Key Light, off Key West
21 NM south-southeast of Looe Key, off Big Pine Key
17 NM southeast of Sombrero Key Light, off Marathon
10 NM southeast of Alligator Reef Light, off Islamorada
 6 NM east-southeast of Molasses Reef Light, off Key Largo
 1 NM east-southeast of Carysfort Reef Light, off Ocean Reef

This data courtesy of the Naval Oceanographic Office.

$$

GMZ031-050830-
Florida Bay including Barnes Sound, Blackwater Sound, and
Buttonwood Sound-
419 PM EDT Fri Sep 4 2026

.TONIGHT...East to southeast winds 5 to 10 knots, increasing to
near 10 knots. Bay waters smooth to a light chop, becoming a light
chop. A chance of showers and thunderstorms.
.SATURDAY...Southeast winds 5 to 10 knots. Bay waters smooth to a
light chop. A chance of showers and thunderstorms.
.SATURDAY NIGHT...East to southeast winds 5 to 10 knots. Bay
waters smooth to a light chop. A chance of showers and
thunderstorms.
.SUNDAY...Southeast to south winds near 5 knots, becoming south to
southwest. Bay waters smooth. A chance of showers and
thunderstorms.
.SUNDAY NIGHT...Southeast to south winds near 5 knots. Bay waters
smooth. A chance of showers and thunderstorms.
.MONDAY...South to southwest winds near 5 knots. Bay waters
smooth. A chance of showers and thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Bay waters
smooth. A chance of showers and thunderstorms.
.TUESDAY...Southeast winds near 5 knots. Bay waters smooth. A
chance of showers and thunderstorms.
.TUESDAY NIGHT...East winds 5 to 10 knots, increasing to near 10
knots. Bay waters smooth to a light chop, becoming a light chop.
A chance of showers and thunderstorms.
.WEDNESDAY AND WEDNESDAY NIGHT...East winds 5 to 10 knots. Bay
waters smooth to a light chop. A chance of showers and
thunderstorms.

$$

GMZ032-035-050830-
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-
419 PM EDT Fri Sep 4 2026

.TONIGHT...Variable winds near 5 knots, becoming east to southeast
and increasing to near 10 knots. Seas 1 foot or less, building to
around 1 foot. Nearshore waters smooth, becoming a light chop. A
chance of showers and thunderstorms.
.SATURDAY...Southeast to south winds 5 to 10 knots. Seas 1 foot
or less. Nearshore waters smooth to a light chop. A chance of
showers and thunderstorms.
.SATURDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
1 foot or less. Nearshore waters smooth to a light chop. A chance
of showers and thunderstorms.
.SUNDAY...Southeast to south winds near 5 knots, becoming south to
southwest. Seas 1 foot or less. Nearshore waters smooth. A chance
of showers and thunderstorms.
.SUNDAY NIGHT...Southeast to south winds near 5 knots. Seas
1 foot or less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.MONDAY...South to southwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Seas
1 foot or less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.TUESDAY...Southeast winds near 5 knots. Seas 1 foot or less.
Nearshore waters smooth. A chance of showers and thunderstorms.
.TUESDAY NIGHT...East 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. A chance of
showers and thunderstorms.
.WEDNESDAY AND WEDNESDAY NIGHT...East winds near 10 knots. Seas
around 1 foot. Nearshore waters a light chop. A chance of showers
and thunderstorms.

$$

GMZ042>044-050830-
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-
419 PM EDT Fri Sep 4 2026

.TONIGHT...Variable winds near 5 knots, becoming southeast and
increasing to near 10 knots. Seas 1 foot or less, building to
around 1 foot. Nearshore waters smooth, becoming a light chop. A
chance of showers and thunderstorms.
.SATURDAY AND SATURDAY NIGHT...East to southeast winds 5 to 10
knots. Seas around 1 foot. Nearshore waters smooth to a light
chop. A chance of showers and thunderstorms.
.SUNDAY...Southeast to south winds near 5 knots, becoming variable.
Seas around 1 foot. Nearshore waters smooth. A chance of showers
and thunderstorms.
.SUNDAY NIGHT...Southeast to south winds near 5 knots. Seas
1 foot or less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.MONDAY...South to southwest winds near 5 knots. Seas 1 foot or
less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Seas 1
foot or less. Nearshore waters smooth. A chance of showers and
thunderstorms.
.TUESDAY...Southeast winds near 5 knots. Seas 1 foot or less.
Nearshore waters smooth. A slight chance of showers and
thunderstorms.
.TUESDAY NIGHT...East winds 5 to 10 knots, increasing to near 10
knots. Seas around 1 foot, building to 1 to 2 feet. Nearshore
waters smooth to a light chop, becoming a light chop. A chance of
showers and thunderstorms.
.WEDNESDAY AND WEDNESDAY NIGHT...East winds near 10 knots. Seas 1
to 2 feet. Nearshore waters a light chop. A chance of showers and
thunderstorms.

$$

GMZ052>055-072>075-050830-
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-
419 PM EDT Fri Sep 4 2026

.TONIGHT...East to southeast winds 5 to 10 knots, increasing to
near 10 knots. Seas around 1 foot, building to 1 to 2 feet. Wave
Detail: East 2 feet at 3 seconds. A chance of showers and
thunderstorms.
.SATURDAY...East to southeast winds 5 to 10 knots. Seas 1 to
2 feet. Wave Detail: East to southeast 2 feet at 4 seconds. A
chance of showers and thunderstorms.
.SATURDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
1 to 2 feet. Wave Detail: East 1 foot at 4 seconds. A chance of
showers and thunderstorms.
.SUNDAY...Southeast to south winds 5 to 10 knots, becoming
variable near 5 knots. Seas 1 to 2 feet, subsiding to around 1
foot. A chance of showers and thunderstorms.
.SUNDAY NIGHT...Southeast to south winds 5 to 10 knots. Seas
1 to 2 feet. A chance of showers and thunderstorms.
.MONDAY...South to south winds near 5 knots. Seas around 1 foot.
A chance of showers and thunderstorms.
.MONDAY NIGHT...Southeast to south winds near 5 knots. Seas
around 1 foot. A chance of showers and thunderstorms.
.TUESDAY...East to southeast winds near 5 knots. Seas around
1 foot. A slight chance of showers and thunderstorms.
.TUESDAY NIGHT...East winds 5 to 10 knots, increasing to near 10
knots. Seas 1 to 2 feet. A chance of showers and thunderstorms.
.WEDNESDAY...East winds near 10 knots. Seas around 2 feet. A
chance of showers and thunderstorms.
.WEDNESDAY NIGHT...East winds 10 to 15 knots. Seas 2 to 3 feet. A
chance of showers and thunderstorms.

$$

GMZ033-034-050830-
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-
419 PM EDT Fri Sep 4 2026

.TONIGHT...East winds near 5 knots, becoming southeast and
increasing to 5 to 10 knots. Seas around 1 foot. Wave Detail:
East to southeast 1 foot at 2 seconds. A chance of showers and
thunderstorms.
.SATURDAY...Southeast winds 5 to 10 knots, becoming variable near
5 knots. Seas 1 foot or less. Wave Detail: East to southeast 1
foot at 3 seconds. A chance of showers and thunderstorms.
.SATURDAY NIGHT...East to southeast winds 5 to 10 knots. Seas
around 1 foot. Wave Detail: East to southeast 1 foot at 3
seconds. A chance of showers and thunderstorms.
.SUNDAY...Southeast winds near 5 knots, becoming variable. Seas 1
foot or less. A chance of showers and thunderstorms.
.SUNDAY NIGHT...Variable winds near 5 knots, becoming southeast to
south. Seas 1 foot or less. A chance of showers and thunderstorms.
.MONDAY...South to southwest winds near 5 knots. Seas 1 foot or
less. A chance of showers and thunderstorms.
.MONDAY NIGHT...Variable winds near 5 knots, becoming southeast to
south. Seas 1 foot or less. A chance of showers and thunderstorms.
.TUESDAY...Southeast to south winds near 5 knots. Seas 1 foot or
less. A chance of showers and thunderstorms.
.TUESDAY NIGHT...East winds 5 to 10 knots. Seas around 1 foot. A
chance of showers and thunderstorms.
.WEDNESDAY...East winds 5 to 10 knots. Seas around 1 foot. A
chance of showers and thunderstorms.
.WEDNESDAY NIGHT...East winds near 10 knots. Seas 1 to 2 feet. A
chance of showers and thunderstorms.

$$

BT/DM