Marine Forecast GMZ005
Expires:202608182100;;928302
FZUS52 KKEY 180859
CWFKEY
Coastal Waters Forecast for the Florida Keys
National Weather Service Key West FL
459 AM EDT Tue Aug 18 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.
GMZ005-182100
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas
459 AM EDT Tue Aug 18 2026
SYNOPSIS
An atlantic ridge axis draped across the coastal waters of the
Florida Keys will maintain a mostly variable wind pattern this
week with wind speeds mainly less than 10 knots. However, brief
increases in wind speeds may occur at times in the evening hours
with winds occasionally approaching 15 knots at times, mostly in
the Upper Keys, so exercise cautionary conditions could briefly
occur. In addition, the presence of saharan air across the Florida
Keys will keep near zero rain chances through the middle of the
week with a very small increase in rain chances by the end of the
week as moisture slowly recovers. The best rain chances late in
the week will typically occur north of the Island Chain in the Bay
and Gulf side waters, though any precipitation activity in
general is expected to be isolated to scattered in nature.
The Approximate Shoreward Edge of the Gulf Stream as of August
13, 2026
38 NM South of Dry Tortugas Lighton Loggerhead Key.
20 NM South of Cosgrove Shoal Lightoff the Marquesas Keys.
17 NM South of Sand Key Lightoff Key West.
21 NM South of Looe Keyoff Big Pine Key.
18 NM Southeast of Sombrero Key Lightoff Marathon.
7 NM Southeast of Alligator Reef Lightoff Islamorada.
7 NM Southeast of Molasses Reef Lightoff Key Largo.
2 NM Southeast of Carysfort Reef Lightoff Ocean Reef.
Gulf Stream Information Courtesy of the National Weather Service in
Key West, using data from RTOFS and NASA SPoRT SST.
All Gulf of Mexico Marine Forecast
- Synopsis for Florida Bay and the Keys
- Florida Bay including Blackwater and Buttonwood Sounds
- Bayside and Gulfside from Craig Key to Halfmoon Shoal out to 5 fathoms
- Gulf waters from East Cape Sable to Chokoloskee 20 to 60 nm out and beyond 5 fathoms
- Gulf of Mexico including Dry Tortugas and Rebecca Shoal Channel
- Hawk Channel from Ocean Reef to Craig Key out to the reef
- 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
- 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 Halfmoon Shoal to GMZ055 20 nm west of Dry Tortugas 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
- Straits of Florida from Halfmoon Shoal to 20 nm west of Dry Tortugas 20 to 60 nm out
- Synopsis for East Cape Sable to Bonita Beach, FL out 60 nm
- Coastal waters from East Cape Sable to Chokoloskee, FL out 20 nm
- Coastal waters from Chokoloskee to Bonita Beach, FL out 20 nm
- Waters from Chokoloskee to Bonita Beach, FL from 20 to 60 nm
- Synopsis for Bonita Beach to Suwannee River, FL out 60 nm
- Coastal waters from Bonita Beach to Englewood FL out 20 nm
- Waters from Bonita Beach to Englewood FL out 20 to 60 nm
- Tampa Bay Waters
- Charlotte Harbor and Pine Island Sound
- Coastal waters from Englewood to Tarpon Springs FL out 20 nm
- Waters from Englewood to Tarpon Springs FL out 20 to 60 nm
- Coastal waters from Tarpon Springs to Suwannee River FL out 20 nm
- Waters from Tarpon Springs to Suwannee River FL out 20 to 60 nm
- Synopsis for Suwannee River to Destin, FL out 60 nm
- Apalachee Bay or Coastal Waters from Keaton Beach to Ochlockonee River FL out to 20 nm
- Coastal waters from Ochlockonee River to Apalachicola, FL out 20 nm
- Waters from Suwannee River to Apalachicola, FL extending from 20 to 60 nm
- Coastal waters from Mexico Beach to Okaloosa Walton County Line FL out 20 NM
- Coastal waters from Mexico Beach to Apalachicola FL out 20 NM
- Coastal waters from Suwanee River to Keaton Beach out 20 nm
- Waters from Mexico Beach to Okaloosa Walton County Line FL from 20 to 60 NM
- Waters from Apalachicola to Mexico Beach FL from 20 to 60 NM
- Synopsis for Destin to Pascagoula, MS out 60 nm
- North Mobile Bay
- South Mobile Bay
- Mississippi Sound
- Perdido Bay Area
- Pensacola Bay Area including Santa Rosa Sound
- Western Choctawhatchee Bay
- Eastern Choctawhatchee Bay
- Coastal waters from Okaloosa Walton County Line FL to Pensacola FL out 20 NM
- Waters from Okaloosa Walton County Line FL to Pensacola FL from 20 to 60 NM
- Coastal Waters from Pensacola FL to Pascagoula MS out 20 nm
- Waters from Pensacola, FL to GMZ670 Pascagoula, MS from 20 to 60 nm
- Synopsis for Pascagoula, MS to Southwest Pass of the Mississippi River out 60 nm
- Lake Pontchartrain/Lake Maurepas
- Mississippi Sound
- Lake Borgne
- Chandeleur Sound
- Coastal Waters from Pascagoula Mississippi to Stake Island Louisiana out 20 nm
- Coastal Waters from Boothville Louisiana to Southwest Pass of the Mississippi River out 20 nm
- Coastal Waters from Pascagoula Mississippi to Stake Island Louisiana from 20 to 60 nm
- Coastal Waters from Stake Island Louisiana to Southwest Pass of the Mississippi River from 20 to 60 nm
- Synopsis for Southwest pass of the Mississippi River to Atchafalaya River, LA out 60 nm
- Coastal Waters from Southwest Pass of the Mississippi River to Port Fourchon Louisiana out 20 nm
- Coastal Waters from Port Fourchon Louisiana to Lower Atchafalaya River Louisiana out 20 Nm
- Coastal Waters from Southwest Pass of the Mississippi River to Port Fourchon Louisiana from 20 to 60 nm
- Coastal Waters from Port Fourchon Louisiana to Lower Atchafalaya River Louisiana from 20 to 60 nm
- Synopsis for Atchafalaya River to High Island, TX out 60 nm
- Coastal waters from Lower Atchafalaya River to Intracoastal City, LA out 20 nm
- Waters from Lower Atchafalaya River to Intracoastal City, LA extending from 20 to 60 nm
- Coastal waters from Intracoastal City, LA to Cameron, LA out 20 nm
- Waters from Intracoastal City, LA to Cameron, LA extending from 20 to 60 nm
- Coastal waters from Cameron, LA to High Island, TX out 20 nm
- Waters from Cameron, LA to High Island, TX extending from 20 to 60 nm
- Sabine Lake
- Calcasieu Lake
- Vermillion Bay
- Synopsis for High Island to Matagorda Ship Channel out 60 nm
- Galveston Bay
- Coastal waters from High Island to Freeport, TX out 20 nm
- Waters from High Island to Freeport, TX extending from 20 to 60 nm
- Matagorda Bay
- Coastal waters from Freeport to Matagorda Ship Channel out 20 nm
- Waters from Freeport to Matagorda Ship Channel, TX extending from 20 to 60 nm
- Synopsis for Matagorda Ship Channel to Baffin Bay, TX out 60 nm
- Bays and Waterways from Port Aransas to Port O’Connor
- Coastal waters Port Aransas to Matagorda Ship Channel out 20 nm
- Waters Port Aransas to Matagorda Ship Channel from 20 to 60 nm
- Bays and Waterways from Baffin Bay to Port Aransas
- Coastal waters Baffin Bay to Port Aransas out 20 nm
- Waters Baffin Bay to Port Aransas from 20 to 60 nm
- Synopsis for Baffin Bay to Rio Grande, TX out 60 nm
- Coastal waters from Baffin Bay to Port Mansfield TX out 20 nm
- Waters from Baffin Bay to Port Mansfield TX from 20 to 60 nm
- Coastal waters from Port Mansfield to Rio Grande River TX out 20 nm
- Waters from Port Mansfield to Rio Grande River TX from 20 to 60 nm
- Laguna Madre from 5nm north of Port Mansfield to Baffin Bay TX
- Laguna Madre from the Arroyo Colorado to 5nm north of Port Mansfield
- Laguna Madre from the Port of Brownsville to the Arroyo Colorado
Gulf of Mexico Marine Watches, Warnings and Advisories Check all Gulf of Mexico Marine Zones.