textproduct: Key West

KEY MESSAGES

- Near normal rain chances (around 30-40%) through tonight will give way to considerably higher rain chances for the remainder of the work week and at least the first half of the weekend.

- Our current confidence in the rainfall totals is low, although most locations in the Keys can generally expect 1 to 3 inches, with locally higher amounts, through Saturday.

- Easterly breezes will trend upwards over the next several days, peaking Wednesday through Thursday (10-15 mph).

AVIATION

(18Z TAFS) Issued at 132 PM EDT Tue Sep 15 2026 While VFR conditions will prevail across the terminals through 18z Wednesday, there will be several opportunities for showers and thunderstorms in the vicinity of the terminals. This includes a developing cloud line near EYW through the late afternoon hours, convection pushing off the Mainland in the evening, and late overnight activity through the remainder of the TAF period in modestly confluent flow. Have elected to include a general window for VCSH for now due to a lack of confidence in evolution, although this will be reevaluated at the 00z TAF issuance.

PREV DISCUSSION

Issued at 400 AM EDT Tue Sep 15 2026 Over the next couple of days, a robust continental high will spread south and southwestward through the southeastern United States and gradually bolster the local pressure gradient. Expect light east to southeasterly breezes to freshen modestly later this afternoon and evening out of the northeast to east. Deep layered moisture is expected to slip slightly through the day with weak lower level inhibition holding on. As a result, expect near normal shower and thunder chances today. Island cloud lines will once again be possible. Temperatures will remain trend less with highs near 90 and lows in the lower 80s. Dew points will hold in the mid 70s.

The tail end of the sharp trough digging off the Atlantic coast is expected to pinch off and interact and absorb a TUTT cell moving in across Hispaniola and the Central Bahamas through the middle portion of the week. As a result, deep layered moisture is expected to increase across and east of our area as broad lower level troughing takes shape. The mid and upper level low and lower level trough is expected to sweep westward into our area through the back half of the week. In addition, the mid and upper low complex will result in falling heights aloft. Expect shower and thunder chances to trend sharply upwards through the middle of the week, likely peaking in the Thursday time frame. Breezes will gradually relax and veer east to southeast as the trough pushes through.

It may take some time for the copious atmospheric moisture to clear out of our area. The trough/low complex should slowly lumber westward into the Gulf while broad ridging sets up off the Atlantic Coast. This will keep a broad moist confluent zone across our area for quite some time. Consequently, a prolonged period of above normal rain chances are possible through late week and weekend. With all that said, the evolution of these features are highly uncertain as is often the case with complex upper level interactions. that said, uncertainty is high and model to model and run to run disagreement is high.

MARINE

Issued at 1030 AM EDT Tue Sep 15 2026 No watches, warnings, or advisories are in effect for the Florida Keys nearshore or offshore waters. From synopsis, light east to southeasterly breezes will gradually back to the northeast to east and freshen this afternoon and evening, as a continental high builds southward towards our area. Expect breezes to peak in the moderate range this evening through late Wednesday. Near normal rain chances will trend considerably upwards through mid week, as broad troughing in the western North Atlantic and increased moisture retrogrades southwestward towards the Keys.

KEY WATCHES/WARNINGS/ADVISORIES

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