NWS Marine Forecast

   GMZ005-212215-  Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas  607 AM EDT Mon Sep 21 2026      .SYNOPSIS...  An upper-level low lingers in the eastern Gulf waters through  tonight but will finally lift away from the area on Tuesday.  However, weather conditions will continue to remain unsettled  throughout most of the week as tropical moisture from the  Caribbean spreads northward into the Keys into the middle of the  week. As a result, rain chances will remain elevated with daily  scattered to numerous showers and thunderstorms. The main hazards  that mariners can expect with this activity will be a daily  occurence with gusty winds, lightning strikes, blinding downpours,  and locally hazardous seas. Breezes will generally remain light  to gentle for most of the week but brief periods of moderate  breezes may occur at times, mainly in the evening and overnight  hours. In addition, winds will be out of the south to southeast  throughout most of the week but winds will start to shift more  northerly by late week and into the weekend as a frontal boundary  gradually pushes southward across coastal waters of the Florida  Keys. Seas will also start to build by the end of the week and  into the weekend as northeasterly swell increases in the wake of  the frontal boundary, especially in the Straits of Florida.    The Approximate Shoreward Edge of the Gulf Stream as of September  15, 2026...    64 NM south-southeast of Dry Tortugas Light, on Loggerhead Key  40 NM south-southeast of Cosgrove Shoal Light, off the Marquesas Keys  36 NM south-southeast of Sand Key Light, off Key West  35 NM southeast of Looe Key, off Big Pine Key  28 NM southeast of Sombrero Key Light, off Marathon  15 NM east-southeast of Alligator Reef Light, off Islamorada  8 NM east-southeast of Molasses Reef Light, off Key Largo  5 NM east-southeast of Carysfort Reef Light, off Ocean Reef    Gulf Stream Information Courtesy of the Naval Oceanographic Office.    $$

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   GMZ033-034-212215-  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-  607 AM EDT Mon Sep 21 2026    TODAY  South to southwest winds 5 to 10 knots. Seas around  1 foot. Wave Detail: South 1 foot at 3 seconds. Showers likely  with a chance of thunderstorms.  TONIGHT  Southeast to south winds 5 to 10 knots. Seas around  1 foot. Wave Detail: Southeast to south 1 foot at 3 seconds.  Showers likely with a chance of thunderstorms.  TUESDAY  South winds 5 to 10 knots. Seas around 1 foot. Wave  Detail: Southeast to south 1 foot at 3 seconds. Showers likely  with a chance of thunderstorms.  TUESDAY NIGHT  Southeast to south winds 5 to 10 knots. Seas  around 1 foot. Showers with a chance of thunderstorms.  WEDNESDAY  South winds 5 to 10 knots. Seas around 1 foot.  Showers with a chance of thunderstorms.  WEDNESDAY NIGHT  Southeast to south winds 5 to 10 knots. Seas  around 1 foot. Showers likely with a chance of thunderstorms.  THURSDAY  Southeast to south winds near 5 knots. Seas 1 foot  or less. Showers likely with a chance of thunderstorms.  THURSDAY NIGHT  East to southeast winds near 5 knots, becoming  north to northeast. Seas 1 foot or less. A chance of showers and  thunderstorms.  FRIDAY  North to northeast winds 5 to 10 knots. Seas 1 to  2 feet. A chance of showers and thunderstorms.  FRIDAY NIGHT  North to northeast winds 5 to 10 knots. Seas 1 to  2 feet. A chance of showers and thunderstorms.    $$