FZUS52 KKEY 120229
CWFKEY

Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
1029 PM EDT Thu Sep 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.

GMZ005-121430
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas 1029 PM EDT Thu Sep 11 2025

SYNOPSIS
A weak surface trough remains draped across South Florida. This will keep a very moist and unsettled environment across our area. A stalled front across Florida is expected to slide southward into the Straits this weekend. As a result, rain chances will remain elevated while winds firm up slightly and clock from northwest to northeast. With that said, there is considerable uncertainty as stronger breezes will not be far off to the north and light and variable breezes are expected just to our east.

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

71 NM South of Dry Tortugas Light...on Loggerhead Key. 42 NM South of Cosgrove Shoal Light...off the Marquesas Keys. 28 NM South of Sand Key Light...off Key West. 12 NM South of Looe Key...off Big Pine Key. 15 NM Southeast of Sombrero Key Light...off Marathon. 14 NM Southeast of Alligator Reef Light...off Islamorada. 11 NM Southeast of Molasses Reef Light...off Key Largo. 7 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.

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GMZ031-121430
Florida Bay including Barnes Sound, Blackwater Sound, and Buttonwood Sound
1029 PM EDT Thu Sep 11 2025

OVERNIGHT
West to northwest winds near 5 knots, becoming variable. Bay waters smooth. Scattered showers and thunderstorms.

FRIDAY
West winds 5 to 10 knots. Bay waters smooth to a light chop. Numerous showers and scattered thunderstorms.

FRIDAY NIGHT
Winds becoming north to northeast near 10 knots. Bay waters becoming a light chop. Numerous showers and scattered thunderstorms.

SATURDAY
North to northeast winds 5 to 10 knots. Bay waters smooth to a light chop. Numerous showers and scattered thunderstorms.

SATURDAY NIGHT
Northeast winds 5 to 10 knots. Bay waters smooth to a light chop. Numerous showers and scattered thunderstorms.

SUNDAY
Variable winds near 5 knots. Bay waters smooth. Scattered showers and thunderstorms.

SUNDAY NIGHT
North to northeast winds 5 to 10 knots. Bay waters smooth to a light chop. Scattered showers and thunderstorms.

MONDAY AND MONDAY NIGHT
Northeast to east winds 5 to 10 knots. Bay waters smooth to a light chop. Scattered showers and thunderstorms.

TUESDAY
Northeast to east winds near 10 knots. Bay waters a light chop. Scattered showers and thunderstorms.

TUESDAY NIGHT
Northeast to east winds 10 to 15 knots. Bay waters a light to moderate chop. Scattered showers and thunderstorms.

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GMZ032-035-121430
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
1029 PM EDT Thu Sep 11 2025

OVERNIGHT
Northwest to north winds near 5 knots, becoming variable. Seas 1 foot or less. Nearshore waters smooth. Scattered showers and thunderstorms.

FRIDAY
Northwest winds 5 to 10 knots. Seas 1 foot or less, except 1 to 2 feet west of the Marquesas Keys. Nearshore waters smooth to a light chop. Numerous showers and scattered thunderstorms.

FRIDAY NIGHT
Winds becoming northeast near 10 knots. Seas around 1 foot, except 1 to 2 feet west of the Marquesas Keys. Nearshore waters becoming a light chop. Numerous showers and scattered thunderstorms.

SATURDAY
North to northeast winds 5 to 10 knots. Seas 1 foot or less, except 1 to 2 feet west of the Marquesas Keys. Nearshore waters smooth to a light chop. Numerous showers and scattered thunderstorms.

SATURDAY NIGHT
Northeast winds 5 to 10 knots. Seas 1 foot or less. Nearshore waters smooth to a light chop. Numerous showers and scattered thunderstorms.

SUNDAY
North to northeast winds 5 to 10 knots. Seas 1 foot or less, except 1 to 2 feet west of the Marquesas Keys. Nearshore waters smooth to a light chop. Scattered showers and thunderstorms.

SUNDAY NIGHT
Winds becoming northeast 5 to 10 knots. Seas 1 foot or less. Nearshore waters becoming smooth to a light chop. Scattered showers and thunderstorms.

MONDAY AND MONDAY NIGHT
Northeast to east winds 5 to 10 knots. Seas 1 foot or less. Nearshore waters smooth to a light chop. Scattered showers and thunderstorms.

TUESDAY
Northeast to east winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. Scattered showers and thunderstorms.

TUESDAY NIGHT
Northeast to east winds 10 to 15 knots. Seas 1 to 2 feet. Nearshore waters a light to moderate chop. Scattered showers and thunderstorms.

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GMZ042>044-121430
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
1029 PM EDT Thu Sep 11 2025

OVERNIGHT
West to northwest winds near 5 knots, becoming variable. Seas 1 foot or less. Nearshore waters smooth. Scattered showers and thunderstorms.

FRIDAY
West to northwest winds near 5 knots. Seas 1 foot or less, except 1 to 2 feet west of Cosgrove Shoal Light. Nearshore waters smooth. Numerous showers and scattered thunderstorms.

FRIDAY NIGHT
Winds becoming northeast 5 to 10 knots. Seas around 1 foot, except 1 to 2 feet west of Cosgrove Shoal Light. Nearshore waters becoming smooth to a light chop. Numerous showers and scattered thunderstorms.

SATURDAY
North to northeast winds 5 to 10 knots. Seas around 1 foot, except 1 to 2 feet west of Cosgrove Shoal Light. Nearshore waters smooth to a light chop. Numerous showers and scattered thunderstorms.

SATURDAY NIGHT
Northeast winds 5 to 10 knots. Seas 1 foot or less. Nearshore waters smooth to a light chop. Numerous showers and scattered thunderstorms.

SUNDAY
North to northeast winds 5 to 10 knots. Seas 1 foot or less. Nearshore waters smooth to a light chop. Scattered showers and thunderstorms.

SUNDAY NIGHT
North to northeast winds 5 to 10 knots. Seas 1 foot or less. Nearshore waters smooth to a light chop. Scattered showers and thunderstorms.

MONDAY
Northeast to east winds 5 to 10 knots. Seas around 1 foot. Nearshore waters smooth to a light chop. Scattered showers and thunderstorms.

MONDAY NIGHT
Northeast to east winds near 10 knots. Seas around 1 foot. Nearshore waters a light chop. Scattered showers and thunderstorms.

TUESDAY
Northeast to east winds increasing to 10 to 15 knots. Seas 1 to 2 feet. Nearshore waters becoming a light to moderate chop. Scattered showers and thunderstorms.

TUESDAY NIGHT
Northeast to east winds 10 to 15 knots. Seas 2 to 3 feet. Nearshore waters a light to moderate chop. Scattered showers and thunderstorms.

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GMZ052>055-072>075-121430
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
1029 PM EDT Thu Sep 11 2025

OVERNIGHT
Northwest winds near 5 knots, becoming variable. Seas 1 to 2 feet. Seas highest off of the Upper Keys due to a north swell. Wave Detail: Northeast to east 1 foot at 3 seconds. Scattered showers and thunderstorms.

FRIDAY
West to northwest winds 5 to 10 knots. Seas 1 to 2 feet. Wave Detail: East 1 foot at 3 seconds. Numerous showers and scattered thunderstorms.

FRIDAY NIGHT
Winds becoming northeast 5 to 10 knots. Seas 1 to 2 feet. Wave Detail: North 1 foot at 3 seconds and northeast 1 foot at 7 seconds. Numerous showers and scattered thunderstorms.

SATURDAY
North winds 5 to 10 knots. Seas 1 to 2 feet. Numerous showers and scattered thunderstorms.

SATURDAY NIGHT
Northeast winds 5 to 10 knots. Seas 1 to 2 feet. Numerous showers and scattered thunderstorms.

SUNDAY
North to northeast winds 5 to 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

SUNDAY NIGHT
North to northeast winds 5 to 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

MONDAY
Northeast to east winds 5 to 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

MONDAY NIGHT
Northeast to east winds near 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

TUESDAY
Northeast to east winds increasing to 10 to 15 knots. Seas building 2 to 3 feet. Scattered showers and thunderstorms.

TUESDAY NIGHT
Northeast to east winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. Scattered showers and thunderstorms.

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GMZ033-034-121430
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
1029 PM EDT Thu Sep 11 2025

OVERNIGHT
Winds becoming variable 5 to 10 knots. Seas building to 1 to 2 feet due to a north swell. Wave Detail: Northwest to north 1 foot at 3 seconds. Numerous showers and scattered thunderstorms.

FRIDAY
North winds 5 to 10 knots. Seas 1 to 2 feet. Wave Detail: Northwest to north 2 feet at 5 seconds. Numerous showers and scattered thunderstorms.

FRIDAY NIGHT
Winds becoming northeast near 10 knots. Seas 1 to 2 feet. Wave Detail: North 2 feet at 4 seconds. Numerous showers and scattered thunderstorms.

SATURDAY
Northeast winds near 10 knots. Seas 1 to 2 feet. Numerous showers and scattered thunderstorms.

SATURDAY NIGHT
Northeast winds near 10 knots. Seas 1 to 2 feet. Numerous showers and scattered thunderstorms.

SUNDAY
North to northeast winds near 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

SUNDAY NIGHT
North to northeast winds near 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

MONDAY AND MONDAY NIGHT
Northeast winds 5 to 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

TUESDAY
Northeast to east winds near 10 knots. Seas 1 to 2 feet. Scattered showers and thunderstorms.

TUESDAY NIGHT
Northeast to east winds 10 to 15 knots. Seas 2 to 3 feet. Scattered showers and thunderstorms.

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MJV