Florida Bay including Blackwater and Buttonwood Sounds Marine Forecast
The Marine Weather Forecast In Detail:
GMZ031 Forecast Issued: 425 PM EST Tue Nov 04 2025
| Tonight...Northeast Winds 15 To 20 Knots, Becoming Northeast To East And Decreasing To 10 To 15 Knots After Midnight. Bay Waters Choppy, Becoming A Light To Moderate Chop. |
| Wednesday...Northeast To East Winds 10 To 15 Knots. Bay Waters A Light To Moderate Chop. |
| Wednesday Night...Northeast To East Winds 10 To 15 Knots, Decreasing To Near 10 Knots. Bay Waters A Light To Moderate Chop, Becoming A Light Chop. Isolated Showers. |
| Thursday...Northeast To East Winds Near 10 Knots. Bay Waters A Light Chop. Isolated Showers. |
| Thursday Night...Northeast To East Winds 10 To 15 Knots Decreasing To 5 To 10 Knots. Bay Waters A Light To Moderate Chop, Becoming Smooth To A Light Chop. Isolated Showers. |
| Friday...Northeast To East Winds 5 To 10 Knots, Becoming East. Bay Waters Smooth To A Light Chop. Isolated Showers. |
| Friday Night...East Winds 5 To 10 Knots, Decreasing To Near 5 Knots. Bay Waters Smooth To A Light Chop, Becoming Smooth. Isolated Showers. |
| Saturday...East Winds Near 5 Knots. Bay Waters Smooth. Isolated Showers. |
| Saturday Night...East Winds 5 To 10 Knots. Bay Waters Smooth To A Light Chop. Isolated Showers. |
| Sunday...East To Southeast Winds Near 5 Knots. Bay Waters Smooth. Isolated Showers. |
| Sunday Night...Northeast Winds Near 5 Knots. Bay Waters Smooth, Becoming Smooth. Isolated Showers. |
| Area Forecast Discussion National Weather Service Key West FL 112pm EST Tuesday Nov 4 2025 Issued at 426am EST Tuesday Nov 4 2025 GOES East Total Precipitable Water (TPW) products shows the Keys in the squeeze play zone. There is higher moisture off to the southeast mainly across the Straits and out to the Bahamas. PWAT (Precipitable Water) values here are being estimated to be between 1.5 to 1.8 inches. Closer to the Island Chain and to the north, the PWAT (Precipitable Water) values are lower between 1.3 to 1.5 inches. This is making for a decent gradient in regards to the moisture across the area. KBYX radar has been detecting showers all night mainly across the Straits of Florida, especially since this is where the deeper moisture has remained overnight. This activity has been generally moving in a northeast to southwest fashion. In the past hour, lightning was observed right at the border of the Keys forecast area across the southern distant Straits of Florida due south of s Wall East Crack. GOES East Nighttime Microphysics shows mostly mid to high level clouds streaming from south to north across the Keys resulting in partly cloudy skies. Temperatures along the Island Chain are in the mid 70s with dew points in the upper 60s to near 70 degrees. In the wake of the cold front last evening, breezy conditions have developed along the Island Chain with Key West and Marathon gusting between 19 to 23 mph over the last few hours. In addition, marine platforms surrounding the Keys have been observing moderate to fresh north to northeast breezes. .FORECAST... Strong high pressure currently centered over the southern Appalachians will continue to slowly traverse to the east through early Wednesday. This high will move offshore sometime Wednesday. As it does so, it will flatten and weaken as it continues moving farther out into the western North Atlantic as we head into late week. This will promote breezy conditions continuing through this evening for the Island Chain with the marine area holding onto the stronger breezes until at least early Wednesday morning. Breezes will continue to slacken to mostly gentle to moderate for late week as another high moves across the eastern United States, albeit, weaker than the current one. Breezes will peak at night into the morning and then most likely lull in the afternoons. As the high continues moving out to sea over the weekend, expect further slackening breezes to light to gentle. Moisture is largely expected to remain across the Straits on south for today through Wednesday keeping rain chances out of the forecast till Wednesday night. Slight moisture return Wednesday night results in slight chances of rain creeping back into the forecast. This moisture will become a little bit deeper late week into the weekend resulting in rain chances ticking up slightly more (~20%). Humidity will also start to increase again late week and especially over the weekend. Model guidance remains in reasonably good agreement outside of timing for a potentially potent cold front early next week. What we know right now is expect another increase in winds leading to another potentially breezier period, cooler temperatures, and significant dip in dew points (humidity). Stay tuned as this could be a fairly significant blow out of the north to northeast for the Florida Keys coastal waters. Marine Issued at 426am EST Tuesday Nov 4 2025 A Small Craft Advisory remains in effect across most of the Florida Keys coastal waters. The exception being Florida Bay and the Bayside/Gulfside waters to the north of the Middle Keys. Small Craft Should Exercise Caution (SCEC) remains headlined for Florida Bay and the Bayside and Gulfside waters. From synopsis, in the wake of the front, strong surface high pressure will slowly migrate eastward across the Southeast U.S. and maintain moderate to fresh breezes through early Wednesday. Thereafter, breezes slacken as the ridge moves out into the Atlantic and weakens. NOAA Key West FL Office: Watches - Warnings - Advisories FL...None. GM...Small Craft Advisory for GMZ042>044-052>055-072>075. |
Key West FL Radar
Southeast Radar