textproduct: Key West

KEY MESSAGES

- Measurable rain chances look to peak overnight, then gradually decreasing through Sunday night and into Monday.

- Conditions will remain seasonably warm and muggy.

- There will be little relief in the warm temperatures overnight, with minimum temperatures near record values in the lower to mid 80s for most communities.

DISCUSSION

Issued at 1024 PM EDT Sat Jun 27 2026 Showers began to flare up over the offshore waters of the Florida Keys in the early evening hours following an early afternoon lull. So far, most thunderstorms were located east of Floyd's Wall or near the Towers. Near surface winds coming off of the Bahamas were converging slightly just outside of our waters, which would provide a source of lift. Thunderstorms over the Gulf were generated by outflow boundaries moving west off of South Florida.

Showers and thunderstorms mostly avoided the island chain this evening. An outflow boundary dissipated near the Upper Keys shortly before sunrise, and MRMS derived data did not calculate measurable precipitation over the islands. That does not mean the atmosphere lacks for moisture. Dew points along the island chain are still in the mid to upper 70s. The KKEY 00Z sounding sampled an environmental PWAT slightly below the 75th percentile for the day. CIMSS derived Total PWAT highlighted 1.8 to 2.0 inches within the air moving towards the Florida Keys, so it would not be a shock if the PWAT increases by tomorrow morning. High resolution models suggest showers will be able to form across the Keys waters during the overnight hours, and popcorn showers are starting to form west of the Florida Keys. Showers in this environment will be quick to develop and collapse. In light of this data, 40% PoPs during the overnight hours feels apt.

MARINE

Issued at 1024 PM EDT Sat Jun 27 2026 No watches, warnings, or advisories are in effect for the Florida Keys coastal waters. From synopsis, a broad high pressure system centered over the North Atlantic will continue to extend westward to the Florida Peninsula through early next week. This will support bouts of light to gentle breezes that may freshen to gentle to moderate at times, mainly in the overnight hours. Starting late Monday, a frontal boundary will press south across the Florida Peninsula and stall across central Florida. This will act to weaken the high and allow for slackening breezes through Wednesday. Thereafter, a broad area of low pressure may develop along the residual stalled frontal boundary and move westward across Florida. This could potentially freshen breezes once again.

AVIATION

(00Z TAFS) Issued at 1024 PM EDT Sat Jun 27 2026 VFR conditions will prevail at EYW and MTH. Moisture will continue to sweep into the Keys overnight and generate scattered showers and thunderstorms. High resolution model returns provide enough confidence to include VCSH for both terminals after midnight. Shower coverage is forecast to decrease tomorrow afternoon. Winds will remain E to SE in the 5 to 10 knot range.

PRELIMINARY POINT TEMPS/POPS

Key West 83 92 84 92 / 40 30 10 10 Marathon 83 89 84 89 / 40 30 10 10

KEY WATCHES/WARNINGS/ADVISORIES

FL...None. GM...None.