GMZ005-182030-
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
1052 AM EDT Sat Apr 18 2026
.SYNOPSIS...High pressure over the central North Atlantic will
start to loosen its grip across the Keys over the weekend. This
will allow for slowly slackening breezes, potentially becoming
variable sometime Sunday/Sunday night. A front approaches the Keys
sometime Monday/Monday evening with a strong high pressure
quickly filling in the wake on Tuesday. Fresh to strong breezes
will prevail as early as Monday night, and hazardous marine
conditions will continue through at least mid week.
The Approximate Shoreward Edge of the Gulf Stream as of April 16...
16 NM South of Dry Tortugas Light...on Loggerhead Key.
12 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
22 NM South of Sand Key Light...off Key West.
30 NM South of Looe Key...off Big Pine Key.
26 NM Southeast of Sombrero Key Light...off Marathon.
20 NM Southeast of Alligator Reef Light...off Islamorada.
15 NM Southeast of Molasses Reef Light...off Key Largo.
9 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.
$$
GMZ033-034-182030- Gulf of America from East Cape Sable to Chokoloskee 20 to 60 NM out and beyond 5 fathoms- Gulf of America including Dry Tortugas and Rebecca Shoal Channel- 1052 AM EDT Sat Apr 18 2026 THIS AFTERNOON East winds near 10 knots, decreasing to 5 to 10 knots. Seas 1 to 2 feet, subsiding to around 1 foot. Wave Detail: East 1 foot at 3 seconds. A slight chance of showers early this morning. TONIGHT East winds 5 to 10 knots. Seas around 1 foot. Wave Detail: East 1 foot at 3 seconds. A slight chance of showers. SUNDAY Northeast to east winds 5 to 10 knots, becoming northwest to north near 10 knots late. Seas around 1 foot. Wave Detail: Northwest to north 1 foot at 2 seconds and northeast to east 1 foot at 3 seconds. SUNDAY NIGHT Northwest to north winds 10 to 15 knots. Seas 1 to 2 feet, building to around 2 feet. MONDAY North to northeast winds 10 to 15 knots, becoming northeast and briefly decreasing to 10 knots in the afternoon. Seas around 2 feet. A slight chance of showers. MONDAY NIGHT Northeast winds 15 to 20 knots, increasing to around 25 knots after midnight. Seas 2 to 3 feet, building to 4 to 6 feet, occasionally to 8 feet. A slight chance of showers. TUESDAY Northeast to east winds near 25 knots, decreasing to 20 to 25 knots. Seas 5 to 7 feet, occasionally to 9 feet. A slight chance of showers. TUESDAY NIGHT Northeast to east winds 20 to 25 knots. Seas 5 to 7 feet, occasionally to 9 feet. WEDNESDAY East winds near 20 knots, briefly decreasing to 10 to 15 knots in the afternoon. Seas 5 to 7 feet, occasionally to 9 feet, subsiding to 3 to 5 feet, occasionally to 6 feet. WEDNESDAY NIGHT East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. A slight chance of showers. $$
GMZ033-034-182030- 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- 1052 AM EDT Sat Apr 18 2026 THIS AFTERNOON East winds near 10 knots, decreasing to 5 to 10 knots. Seas 1 to 2 feet, subsiding to around 1 foot. Wave Detail: East 1 foot at 3 seconds. A slight chance of showers early this morning. TONIGHT East winds 5 to 10 knots. Seas around 1 foot. Wave Detail: East 1 foot at 3 seconds. A slight chance of showers. SUNDAY Northeast to east winds 5 to 10 knots, becoming northwest to north near 10 knots late. Seas around 1 foot. Wave Detail: Northwest to north 1 foot at 2 seconds and northeast to east 1 foot at 3 seconds. SUNDAY NIGHT Northwest to north winds 10 to 15 knots. Seas 1 to 2 feet, building to around 2 feet. MONDAY North to northeast winds 10 to 15 knots, becoming northeast and briefly decreasing to 10 knots in the afternoon. Seas around 2 feet. A slight chance of showers. MONDAY NIGHT Northeast winds 15 to 20 knots, increasing to around 25 knots after midnight. Seas 2 to 3 feet, building to 4 to 6 feet, occasionally to 8 feet. A slight chance of showers. TUESDAY Northeast to east winds near 25 knots, decreasing to 20 to 25 knots. Seas 5 to 7 feet, occasionally to 9 feet. A slight chance of showers. TUESDAY NIGHT Northeast to east winds 20 to 25 knots. Seas 5 to 7 feet, occasionally to 9 feet. WEDNESDAY East winds near 20 knots, briefly decreasing to 10 to 15 knots in the afternoon. Seas 5 to 7 feet, occasionally to 9 feet, subsiding to 3 to 5 feet, occasionally to 6 feet. WEDNESDAY NIGHT East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. A slight chance of showers. $$