GMZ005-220930-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
430 PM EST Wed Jan 21 2026
.SYNOPSIS...A broad high pressure system located just off the
Mid-Atlantic will continue slowly weaken as it slides further
eastward through the rest of the work week. Breezes will slacken
as the pressure gradient weakens, and gentle to moderate breezes
are expected across the nearshore and offshore waters for Thursday
through Saturday, becoming light to gentle for Sunday. A strong
winter storm will impact the Southeast over the weekend, driving a
strong frontal boundary through the Keys marine zones Monday
afternoon and evening. Winds will clock around to the north in its
wake for early next week, becoming fresh to strong.
The Approximate Shoreward Edge of the Gulf Stream as of January
18...
18 NM South of Dry Tortugas Light...on Loggerhead Key.
16 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
15 NM South of Sand Key Light...off Key West.
13 NM South of Looe Key...off Big Pine Key.
13 NM Southeast of Sombrero Key Light...off Marathon.
12 NM Southeast of Alligator Reef Light...off Islamorada.
7 NM Southeast of Molasses Reef Light...off Key Largo.
4 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 and RTOFS.
$$
GMZ032-035-220930- 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- 430 PM EST Wed Jan 21 2026 SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL WINDS DECREASE TONIGHT Northeast winds 15 to 20 knots, decreasing to 10 to 15 knots. Seas subsiding to 1 to 2 feet, except subsiding to 2 to 3 feet west of the Marquesas Keys. Nearshore waters choppy, becoming a light to moderate chop. Isolated showers. THURSDAY Northeast winds 10 to 15 knots, decreasing to near 10 knots. Seas 1 to 2 feet, except 2 to 3 feet west of the Marquesas Keys. Nearshore waters a light to moderate chop, becoming a light chop. Isolated showers. THURSDAY NIGHT Northeast to east winds near 10 knots. Seas 1 to 2 feet, except around 2 feet west of the Marquesas Keys. Nearshore waters a light chop. Isolated showers. FRIDAY Northeast to east winds 5 to 10 knots. Seas 1 to 2 feet. Nearshore waters smooth to a light chop. Isolated showers. FRIDAY NIGHT Northeast to east winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. SATURDAY East winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. SATURDAY NIGHT East to southeast winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. SUNDAY Southeast winds near 10 knots, decreasing to 5 to 10 knots. Seas 1 to 2 feet, subsiding to around 1 foot. Nearshore waters a light chop, becoming a smooth to a light chop. SUNDAY NIGHT East to southeast winds 5 to 10 knots. Seas around 1 foot. Nearshore waters smooth to a light chop. MONDAY Northwest to north 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. Isolated showers. MONDAY NIGHT North winds 10 to 15 knots, increasing to near 15 knots. Seas 1 to 2 feet, building to 2 to 4 feet, occasionally to 5 feet. West of the Marquesas Keys, seas 2 to 3 feet, building to 4 to 7 feet, occasionally to 9 feet. Nearshore waters a light to moderate chop, becoming a moderate chop. Isolated showers. $$
GMZ032-035-220930- 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- 430 PM EST Wed Jan 21 2026 SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL WINDS DECREASE TONIGHT Northeast winds 15 to 20 knots, decreasing to 10 to 15 knots. Seas subsiding to 1 to 2 feet, except subsiding to 2 to 3 feet west of the Marquesas Keys. Nearshore waters choppy, becoming a light to moderate chop. Isolated showers. THURSDAY Northeast winds 10 to 15 knots, decreasing to near 10 knots. Seas 1 to 2 feet, except 2 to 3 feet west of the Marquesas Keys. Nearshore waters a light to moderate chop, becoming a light chop. Isolated showers. THURSDAY NIGHT Northeast to east winds near 10 knots. Seas 1 to 2 feet, except around 2 feet west of the Marquesas Keys. Nearshore waters a light chop. Isolated showers. FRIDAY Northeast to east winds 5 to 10 knots. Seas 1 to 2 feet. Nearshore waters smooth to a light chop. Isolated showers. FRIDAY NIGHT Northeast to east winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. SATURDAY East winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. SATURDAY NIGHT East to southeast winds near 10 knots. Seas 1 to 2 feet. Nearshore waters a light chop. SUNDAY Southeast winds near 10 knots, decreasing to 5 to 10 knots. Seas 1 to 2 feet, subsiding to around 1 foot. Nearshore waters a light chop, becoming a smooth to a light chop. SUNDAY NIGHT East to southeast winds 5 to 10 knots. Seas around 1 foot. Nearshore waters smooth to a light chop. MONDAY Northwest to north 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. Isolated showers. MONDAY NIGHT North winds 10 to 15 knots, increasing to near 15 knots. Seas 1 to 2 feet, building to 2 to 4 feet, occasionally to 5 feet. West of the Marquesas Keys, seas 2 to 3 feet, building to 4 to 7 feet, occasionally to 9 feet. Nearshore waters a light to moderate chop, becoming a moderate chop. Isolated showers. $$