Coastal Waters Forecast
Issued by NWS Key West, FL
Issued by NWS Key West, FL
442 FZUS52 KKEY 280225 CWFKEY Coastal Waters Forecast for the Florida Keys National Weather Service Key West FL 1025 PM EDT Sun Sep 27 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. GMZ005-281430- Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas 1025 PM EDT Sun Sep 27 2026 .SYNOPSIS... A Nor`easter in the vicinity of New Jersey which will continue to support a northeasterly swell with large periods in the eastern marine zones through overnight, before subsiding tomorrow. A weak frontal boundary will begin to push back northward through the marine zones on Monday. Winds will then clock back to the southeast to south for early this week, also accompanied by increasing rain and thunder chances. In addition, strengthening high pressure is expected to move off the Southeast U.S. coastline around the middle to latter half of next week, merging with the Atlantic high. This will promote freshening east to southeast breezes, potentially become moderate to fresh. The Approximate Shoreward Edge of the Gulf Stream as of September 25, 2026... 43 NM south of Dry Tortugas Light, on Loggerhead Key 20 NM south of Cosgrove Shoal Light, off the Marquesas Keys 14 NM south of Sand Key Light, off Key West 7 NM south-southeast of Looe Key, off Big Pine Key 4 NM south-southeast of Sombrero Key Light, off Marathon 4 NM south-southeast of Alligator Reef Light, off Islamorada 0 NM southeast of Molasses Reef Light, off Key Largo 1 NM west-northwest of Carysfort Reef Light, off Ocean Reef Gulf Stream Information Courtesy of the Naval Oceanographic Office. $$ GMZ031-281430- Florida Bay including Barnes Sound, Blackwater Sound, and Buttonwood Sound- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West winds near 10 knots, decreasing to near 5 knots late. Bay waters a light chop, becoming smooth. .MONDAY...Variable winds near 5 knots, becoming southwest to west. Bay waters smooth. A slight chance of showers and thunderstorms. .MONDAY NIGHT...Southwest winds near 5 knots, becoming light and variable. Bay waters smooth. A chance of showers and thunderstorms. .TUESDAY...Variable winds near 5 knots, becoming southeast. Bay waters smooth. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Bay waters smooth to a light chop. Showers likely with a chance of thunderstorms. .WEDNESDAY...East winds near 10 knots, increasing to 10 to 15 knots. Bay waters a light chop, becoming a light to moderate chop. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds 10 to 15 knots. Bay waters a light to moderate chop. A chance of thunderstorms. Showers likely. .THURSDAY...East winds 10 to 15 knots, increasing 15 to 20 knots. Bay waters a light to moderate chop, becoming choppy. A chance of thunderstorms. Showers likely. .THURSDAY NIGHT...East winds 15 to 20 knots, decreasing to 10 to 15 knots. Bay waters choppy, becoming a light to moderate chop. A chance of showers and thunderstorms. .FRIDAY...East to southeast winds 10 to 15 knots. Bay waters a light to moderate chop. A chance of thunderstorms. Showers likely. .FRIDAY NIGHT...East to southeast winds 10 to 15 knots. Bay waters a light to moderate chop. A chance of showers and thunderstorms. $$ GMZ032-035-281430- 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- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West winds near 10 knots, decreasing to near 5 knots. Seas around 1 foot. Nearshore waters a light chop, becoming smooth. .MONDAY...Variable winds near 5 knots, becoming southwest to south. Seas 1 foot or less. Nearshore waters smooth. A slight chance of showers and thunderstorms. .MONDAY NIGHT...Southeast to south winds near 5 knots, becoming variable. Seas 1 foot or less. Nearshore waters smooth. Showers likely with a chance of thunderstorms. .TUESDAY...Variable winds near 5 knots, becoming east to southeast. Seas 1 foot or less. Nearshore waters smooth. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas 1 foot or less. Nearshore waters smooth to a light chop. Showers likely with a chance of thunderstorms. .WEDNESDAY...East to southeast winds near 10 knots, increasing to 10 to 15 knots. Seas 1 foot or less, building to around 1 foot. Nearshore waters a light chop, becoming a light to moderate chop. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds near 15 knots. Seas 1 to 2 feet. Nearshore waters a moderate chop. Showers likely with a chance of thunderstorms. .THURSDAY...East winds 15 to 20 knots. Seas 1 to 2 feet, except around 3 feet west of the Marquesas Keys. Nearshore waters choppy. Showers likely with a chance of thunderstorms. .THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas 1 to 2 feet, except around 3 feet west of the Marquesas Keys. Nearshore waters choppy. Showers likely with a chance of thunderstorms. .FRIDAY...East to southeast winds 15 to 20 knots. Seas 1 to 2 feet, except 2 to 3 feet west of the Marquesas Keys. Nearshore waters choppy. A chance of thunderstorms. Showers likely. .FRIDAY NIGHT...East to southeast winds 10 to 15 knots. Seas 2 to 3 feet. Nearshore waters a light to moderate chop. A chance of showers and thunderstorms. $$ GMZ042-281430- Hawk Channel from Ocean Reef to Craig Key out to the reef- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West winds 10 to 15 knots, decreasing to near 5 knots late. Seas around 2 feet, subsiding to around 1 foot. Nearshore waters a light to moderate chop, becoming smooth. .MONDAY...Southwest to west winds near 5 knots. Seas 1 foot or less. Nearshore waters smooth. A slight chance of showers and thunderstorms. .MONDAY NIGHT...Southwest to west winds near 5 knots. Seas 1 foot or less. Nearshore waters smooth. A chance of showers and thunderstorms. .TUESDAY...Variable winds near 5 knots, becoming east. Seas 1 foot or less. Nearshore waters smooth. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas around 1 foot. Nearshore waters smooth to a light chop. Showers likely with a chance of thunderstorms. .WEDNESDAY...East winds near 10 knots, increasing to 10 to 15 knots. Seas around 1 foot, building to 1 to 2 feet. Nearshore waters a light chop, becoming a light to moderate chop. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds near 15 knots. Seas 1 to 2 feet, building 2 to 3 feet. Nearshore waters a moderate chop. A chance of thunderstorms. Showers. .THURSDAY...East winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Nearshore waters choppy. A chance of thunderstorms. Showers likely. .THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Nearshore waters choppy. Showers likely with a chance of thunderstorms. .FRIDAY...East to southeast winds near 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. Nearshore waters a moderate chop. Showers likely with a chance of thunderstorms. .FRIDAY NIGHT...East to southeast winds 10 to 15 knots. Seas 2 to 3 feet. Nearshore waters a light to moderate chop. A chance of showers and thunderstorms. $$ GMZ043-044-281430- 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- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West to northwest winds near 10 knots, decreasing to near 5 knots. Seas around 1 foot. Nearshore waters a light chop, becoming smooth. .MONDAY...Variable winds near 5 knots, becoming south to southwest. Seas 1 foot or less. Nearshore waters smooth. A chance of showers with a slight chance of thunderstorms. .MONDAY NIGHT...Southeast to south winds near 5 knots. Seas 1 foot or less. Nearshore waters smooth. Showers likely with a chance of thunderstorms. .TUESDAY...Variable winds near 5 knots, becoming east to southeast. Seas 1 foot or less. Nearshore waters smooth. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast 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. Showers likely with a chance of thunderstorms. .WEDNESDAY...East to southeast winds near 10 knots, increasing to 10 to 15 knots. Seas around 1 foot, building to 1 to 2 feet. Nearshore waters a light chop, becoming a light to moderate chop. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds 15 to 20 knots. Seas 1 to 3 feet, building 2 to 4 feet, occasionally to 5 feet. Nearshore waters choppy. A chance of showers and thunderstorms. .THURSDAY...East to southeast winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Nearshore waters choppy. A chance of showers and thunderstorms. .THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Nearshore waters choppy. Showers likely with a chance of thunderstorms. .FRIDAY...East to southeast winds 15 to 20 knots. Seas 2 to 4 feet, occasionally to 5 feet. Nearshore waters choppy. A chance of thunderstorms. A chance of showers. .FRIDAY NIGHT...East to southeast winds 10 to 15 knots. Seas 2 to 3 feet. Nearshore waters a light to moderate chop. A chance of showers and thunderstorms. $$ GMZ052-072-281430- Straits of Florida from Ocean Reef to Craig Key out 20 NM- Straits of Florida from Ocean Reef to Craig Key 20 to 60 NM out- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West winds 10 to 15 knots, decreasing to near 5 knots late. Seas 2 to 4 feet, subsiding to 1 to 2 feet. Wave Detail: North to northeast 2 feet at 13 seconds. A slight chance of showers. .MONDAY...Southwest to west winds near 5 knots. Seas 1 to 2 feet. Wave Detail: North to northeast 1 foot at 12 seconds. A slight chance of showers and thunderstorms. .MONDAY NIGHT...South to southwest winds near 5 knots, becoming variable. Seas 1 to 2 feet, subsiding to around 1 foot. Wave Detail: North to northeast 1 foot at 11 seconds. Showers likely with a chance of thunderstorms. .TUESDAY...Variable near 5 knots, becoming southeast to east and increasing to 5 to 10 knots. Seas around 1 foot. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas around 1 foot, building 1 to 2 feet. Showers likely with a chance of thunderstorms. .WEDNESDAY...East winds 10 to 15 knots. Seas 1 to 2 feet, building 2 to 3 feet. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds near 15 knots, increasing to 15 to 20 knots. Seas 3 to 4 feet, building to 4 to 5 feet, occasionally to 6 feet. Showers with a chance of thunderstorms. .THURSDAY...East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. Showers likely with a chance of thunderstorms. .THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas around 4 feet, occasionally to 5 feet. Showers likely with a chance of thunderstorms. .FRIDAY...East to southeast winds 15 to 20 knots, becoming 10 to 15 knots in the afternoon. Seas 3 to 5 feet, occasionally to 6 feet. A chance of showers and thunderstorms. .FRIDAY NIGHT...East to southeast winds 10 to 15 knots. Seas around 3 feet. A chance of showers and thunderstorms. $$ GMZ053>055-073>075-281430- 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 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- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West to northwest winds 5 to 10 knots, becoming variable and decreasing to near 5 knots late. Seas 1 to 2 feet, subsiding to around 1 foot. Wave Detail: Northeast to east 1 foot at 4 seconds and northwest to north 1 foot at 4 seconds. A slight chance of showers. .MONDAY...Variable winds near 5 knots, becoming south to southeast. Seas around 1 foot. Wave Detail: North to northeast 1 foot at 4 seconds. A chance of showers with a slight chance of thunderstorms. .MONDAY NIGHT...Southeast to south winds near 5 knots. Seas around 1 foot. Showers likely with a chance of thunderstorms. .TUESDAY...Variable winds near 5 knots, becoming east to southeast and increasing to 5 to 10 knots. Seas around 1 foot. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast winds 5 to 10 knots, increasing to near 10 knots. Seas around 1 foot, building to 1 to 2 feet. Showers likely with a chance of thunderstorms. .WEDNESDAY...East to southeast winds near 10 knots, becoming east and increasing to 10 to 15 knots. Seas 1 to 2 feet, building 2 to 3 feet. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds near 15 knots, increasing to 15 to 20 knots. Seas 3 to 4 feet, building to 4 to 5 feet, occasionally to 6 feet. Showers with a chance of thunderstorms. .THURSDAY...East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. Showers with a chance of thunderstorms. .THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. Showers likely with a chance of thunderstorms. .FRIDAY...East to southeast winds 15 to 20 knots. Seas 3 to 5 feet, occasionally to 6 feet. A chance of showers and thunderstorms. .FRIDAY NIGHT...East to southeast winds near 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. A chance of showers and thunderstorms. $$ GMZ033-034-281430- Gulf of America from East Cape Sable to Chokoloskee 20 to 60 NM out and beyond 5 fathoms- Gulf of America including Dry Tortugas and Rebecca Shoal Channel- 1025 PM EDT Sun Sep 27 2026 .OVERNIGHT...West to northwest winds 5 to 10 knots, becoming variable and decreasing to near 5 knots. Seas around 1 foot. Wave Detail: Northwest to north 1 foot at 4 seconds. .MONDAY...Variable winds near 5 knots, becoming south. Seas 1 foot or less. Wave Detail: Northwest to north 1 foot at 4 seconds. A slight chance of showers and thunderstorms. .MONDAY NIGHT...Southeast to south winds near 5 knots. Seas 1 foot or less. Showers likely with a chance of thunderstorms. .TUESDAY...Southeast winds near 5 knots, increasing to 5 to 10 knots. Seas 1 foot or less, building to around 1 foot. Showers likely with a chance of thunderstorms. .TUESDAY NIGHT...East to southeast winds 5 to 10 knots. Seas around 1 foot. Showers likely with a chance of thunderstorms. .WEDNESDAY...East to southeast winds near 10 knots, increasing to 10 to 15 knots. Seas around 1 foot, building to 1 to 2 feet. Showers likely with a chance of thunderstorms. .WEDNESDAY NIGHT...East winds near 15 knots, increasing 15 to 20 knots. Seas 2 to 3 feet. Showers with a chance of thunderstorms. .THURSDAY...East to southeast winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Showers with a chance of thunderstorms. .THURSDAY NIGHT...East to southeast winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Showers likely with a chance of thunderstorms. .FRIDAY...East to southeast winds 15 to 20 knots. Seas 2 to 4 feet, occasionally to 5 feet. A chance of thunderstorms. Showers likely. .FRIDAY NIGHT...East to southeast winds near 15 knots. Seas 2 to 3 feet. A chance of showers and thunderstorms. $$ MJV