textproduct: Key West

KEY MESSAGES

- Major coastal flooding in the Upper Keys and minor to moderate coastal flooding in the Lower to Middle Keys is ongoing, especially around high tide.

- Small Craft Advisory remains in effect for all the Florida Keys coastal waters. A Gale Watch is in effect for the Straits of Florida and the SE Gulf waters from early Monday morning through early Tuesday morning. - Fast-moving showers and isolated thunderstorms are moving through the area, and will continue through at least Tuesday night. Any of this activity will be capable of producing stronger wind gusts.

DISCUSSION

Issued at 1037 AM EDT Sun Oct 25 2026 The day began with relatively drier conditions across the Florida Keys. KBYX radar returns identified most of the showers were over the eastern Straits of Florida. However, daytime heating and broad wind convergence over the Outer Gulf allowed shallow showers to form over the western waters. GOES East satellite scans, meanwhile, show a broad upper altitude trough over the Bahamas, Cuba, and South Florida with its dry side located over the Florida Keys. Last night's sounding, which sampled an environmental PWAT below 1.00 inches, lined up well with this feature. Advected Layer PWAT also helped illustrate why and where showers were able to form. The upper level trough happens to be vertically stacked, and 700-500 mb PWAT scans are able to track a dry slot wrapping around the low over the central part of the CWA. A shift to a more moist region wrapping over the Keys offers an explanation as to why the 12Z KKEY sounding sampled an environment where the PWAT rose by a quarter of an inch. Low level moisture exists in the environment for showers to form. The challenge will be when and where.

This morning, mostly sunny skies along the island chain allowed temperatures to rise into the upper 70s. Dew points are still hovering around 70 F. Breezes have oscillated between moderate to fresh and fresh to strong over the water. Based on these observations, one could assume persistence and say that the environment is not likely to change. The problem is that last night, we upgraded the Small Craft Advisory over the offshore marine zones to a Gale Watch. A high pressure system is building over the eastern United States while a surface reflection of the upper level trough continues to spin north of Hispaniola. Breezes are forecast to rapidly freshen during the afternoon hours per convective models and statistical guidance. In addition, northeasterly winds will be able to direct additional moisture towards the Florida Keys. Showers are more likely over the Upper Keys compared to the Lower and Middle Keys, and unfortunately that may overlap with the time of high tides. Keep an eye on the radar, watch the winds across the Keys, and enjoy the last Sunday of October!

MARINE

Issued at 1037 AM EDT Sun Oct 25 2026 A Small Craft Advisory remains in effect for all the Florida Keys coastal waters. A Gale Watch is now in effect for the Straits of Florida and the SE Gulf waters from early Monday morning through early Tuesday morning for the potential for frequent gusts to near 35 knots even outside of shower or storm activity.

From synopsis, a Small Craft Advisory is in effect for all Florida Keys marine zones along with a Gale Watch for the Straits of Florida and the SE Gulf Waters for early Monday morning through early Tuesday morning. High pressure over the eastern United States and a weak low northeast of the Bahamas will sustain fresh to strong breezes through the weekend and early next week. Peak breezes are expected tonight through Tuesday. Near gale wind gusts will be possible over the Outer Gulf waters and the Florida Straits. Freshening breezes and pulses of low level moisture will support elevated shower chances tonight and Monday. Breezes are on track to slacken to moderate to fresh by midweek.

AVIATION

(12Z TAFS) Issued at 1037 AM EDT Sun Oct 25 2026 VFR VIS and CIGs conditions will prevail at EYW and MTH. Cloud cover will slowly increase during the afternoon, there is high confidence any CIGs will remain safely above VFR flight levels. Near surface winds are on track to increase during the afternoon with frequent near gale force gusts by the overnight hours. Showers that do form will be fast moving. There is not enough confidence at this time to include a TEMPO or PROB30 group.

CLIMATE

On this day in 1903, the daily record cold high temperature of 70F was recorded in Key West. This also tied for the coldest high temperature ever recorded in October. Temperature records for Key West date back to 1872.

PRELIMINARY POINT TEMPS/POPS

Key West 83 75 84 75 / 30 40 30 20 Marathon 83 75 84 75 / 30 40 30 20

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Warning until 5 AM EDT Monday for FLZ076.

Coastal Flood Advisory until 5 AM EDT Monday for FLZ077-078.

GM...Small Craft Advisory until 5 AM EDT Tuesday for GMZ031-032-035- 042>044.

Small Craft Advisory until 5 AM EDT Monday for GMZ033-034- 052>055-072>075.

Gale Watch from late tonight through late Monday night for GMZ033-034-052>055-072>075.