textproduct: Key West

KEY MESSAGES

- Fresh to strong breezes will continue in the wake of the front. A Small Craft Advisory remains in effect for all Keys coastal waters.

- Rain and thunderstorm chances will increase Thursday through Friday, followed by diminished breezes this weekend.

DISCUSSION

Issued at 959 PM EDT Tue Apr 21 2026 Water vapor imagery highlights a stormy Pacific Northwest giving way to mostly zonal flow across the eastern two-thirds of the CONUS. A 1027 mb high pressure system centered over the extreme western North Atlantic supports strong northeast to east breezes (22-27 knots) across the Florida Keys this evening, although magnitudes have eased a few knots since this afternoon. Temperatures are in the mid 70s and dewpoints are in the upper 50s to lower 60s. The 00Z KKEY RAOB sampled a well mixed boundary layer beneath of strong inversion based near 900 mb. The forecast calls for breezes to ease a bit more overnight with low temperatures in the lower 70s by morning. Rain chances are nil for the island chain. No changes are needed nor planned for the this forecast cycle.

The forecast for the remainder of the week will focus on the trimming of Small Craft Advisories, followed by increased rain/thunder chances in the Thursday through Friday night timeframe. The pattern suggests mesoscale steering mechanisms enhanced by a mid to upper level low in the southern stream flow. A pattern like this, this time of year, suggests a chance for thunderstorms.

MARINE

Issued at 959 PM EDT Tue Apr 21 2026 Small Craft Advisories remain in effect for all coastal waters of the Florida Keys due to northeast to east winds of 20 to 25 knots. From synopsis, fresh to strong northeast to east breezes will continue through Wednesday as high pressure builds across the Eastern Seaboard in the wake of last evenings front. This high will continue to slowly migrate into the western North Atlantic over the next several days. As the high slowly weakens, breezes will begin to slacken by Thursday. Gentle to moderate breezes are expected for Friday and Saturday.

AVIATION

(00Z TAFS) Issued at 959 PM EDT Tue Apr 21 2026 VFR and gusty northeast to east breezes will prevail at the EYW and MTH terminals overnight.

PRELIMINARY POINT TEMPS/POPS

Key West 72 79 71 80 / 10 10 20 30 Marathon 72 80 72 81 / 10 0 20 30

KEY WATCHES/WARNINGS/ADVISORIES

FL...None. GM...Small Craft Advisory until 6 AM EDT Wednesday for GMZ031>035- 042>044-052>055-072>075.