GMZ005-090830-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
420 PM EDT Thu Oct 8 2026
.SYNOPSIS...Hurricane Isaias, currently over the southwestern
Gulf waters, is expected to move towards the North Gulf Coast over
the next few days, strengthening as it does so. Enhanced swell
generated by the hurricane will increase wave heights in the
western Florida Straits and Gulfside waters tonight through the
first half of the weekend. A stationary front remains draped
across north-central Florida which will slowly drift southward
infringing on the surface ridge to its south. Breezes are expected
to freshen before the weekend in response with moderate to fresh
breezes possible in the western waters. A plume of moisture will
also move into the Florida Keys at the same time and increase
shower and thunderstorm chances.
The Approximate Shoreward Edge of the Gulf Stream as of October
2, 2026...
39 NM south-southeast of Dry Tortugas Light, on Loggerhead Key
14 NM south-southeast of Cosgrove Shoal Light, off the Marquesas Keys
8 NM south-southeast of Sand Key Light, off Key West
2 NM south-southeast of Looe Key, off Big Pine Key
1 NM south-southeast of Sombrero Key Light, off Marathon
0 NM south-southeast of Alligator Reef Light, off Islamorada
2 NM northwest of Molasses Reef Light, off Key Largo
2 NM northwest of Carysfort Reef Light, off Ocean Reef
Gulf Stream Information Courtesy of the Naval Oceanographic Office.
$$
GMZ052>054-072>074-090830- 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 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- 420 PM EDT Thu Oct 8 2026 TONIGHT Southeast winds 5 to 10 knots, increasing to 10 to 15 knots. Seas 1 to 2 feet, building to 2 to 3 feet. Wave Detail: Southeast 2 feet at 4 seconds. A slight chance of showers and thunderstorms. FRIDAY Southeast winds 10 to 15 knots. Seas 2 to 3 feet, building to 2 to 4 feet west of the Marquesas Keys. Wave Detail: East to southeast 3 feet at 4 seconds and southwest to west 2 feet at 11 seconds. A chance of showers with a slight chance of thunderstorms. FRIDAY NIGHT Southeast winds 10 to 15 knots. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East to southeast 4 feet at 5 seconds and southwest to west 3 feet at 10 seconds. Showers likely with a slight chance of thunderstorms. SATURDAY Southeast winds 10 to 15 knots. Seas subsiding to 3 to 4 feet, occasionally to 5 feet. A chance of showers with a slight chance of thunderstorms. SATURDAY NIGHT East to southeast winds 10 to 15 knots, increasing to near 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. A chance of showers with a slight chance of thunderstorms. SUNDAY East to southeast winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. A slight chance of showers and thunderstorms. SUNDAY NIGHT East winds 10 to 15 knots. Seas 2 to 3 feet. MONDAY Northeast to east winds near 10 knots. Seas 2 to 3 feet. A slight chance of showers. MONDAY NIGHT Northeast to east winds near 10 knots. Seas 1 to 2 feet. A slight chance of showers and thunderstorms. TUESDAY Northeast winds 5 to 10 knots. Seas 1 to 2 feet. A slight chance of showers. TUESDAY NIGHT Northeast to east winds 5 to 10 knots. Seas building to 2 to 3 feet due to increasing swell. A chance of showers with a slight chance of thunderstorms. $$
GMZ052>054-072>074-090830- 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 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- 420 PM EDT Thu Oct 8 2026 TONIGHT Southeast winds 5 to 10 knots, increasing to 10 to 15 knots. Seas 1 to 2 feet, building to 2 to 3 feet. Wave Detail: Southeast 2 feet at 4 seconds. A slight chance of showers and thunderstorms. FRIDAY Southeast winds 10 to 15 knots. Seas 2 to 3 feet, building to 2 to 4 feet west of the Marquesas Keys. Wave Detail: East to southeast 3 feet at 4 seconds and southwest to west 2 feet at 11 seconds. A chance of showers with a slight chance of thunderstorms. FRIDAY NIGHT Southeast winds 10 to 15 knots. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East to southeast 4 feet at 5 seconds and southwest to west 3 feet at 10 seconds. Showers likely with a slight chance of thunderstorms. SATURDAY Southeast winds 10 to 15 knots. Seas subsiding to 3 to 4 feet, occasionally to 5 feet. A chance of showers with a slight chance of thunderstorms. SATURDAY NIGHT East to southeast winds 10 to 15 knots, increasing to near 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. A chance of showers with a slight chance of thunderstorms. SUNDAY East to southeast winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. A slight chance of showers and thunderstorms. SUNDAY NIGHT East winds 10 to 15 knots. Seas 2 to 3 feet. MONDAY Northeast to east winds near 10 knots. Seas 2 to 3 feet. A slight chance of showers. MONDAY NIGHT Northeast to east winds near 10 knots. Seas 1 to 2 feet. A slight chance of showers and thunderstorms. TUESDAY Northeast winds 5 to 10 knots. Seas 1 to 2 feet. A slight chance of showers. TUESDAY NIGHT Northeast to east winds 5 to 10 knots. Seas building to 2 to 3 feet due to increasing swell. A chance of showers with a slight chance of thunderstorms. $$