textproduct: Key West

KEY MESSAGES

- High moisture content across the region will support daily chances for showers and thunderstorms through the weekend.

- Temperatures will be seasonably warm, with highs near 90, and lows in the lower 80s.

DISCUSSION

Issued at 1111 AM EDT Thu Sep 3 2026 The 12z morning sounding at KEY sampled a mean steering flow out of the south to southwest at near 10 knots. GOES-19 visible satellite imagery, CIMSS satellite-derived total precipitable water product, and KBYX Doppler radar imagery reflects this flow direction, with a noticeable arching dry layer approaching the Florida Keys in the Straits of Florida. As is often the case, on the leading edge of this Cuban-influenced dry air, there is a proliferation of shower and thunderstorm activity ahead of the dry air, mainly in the Gulf waters north of the Lower Keys.

For the rest of today, we are anticipating the dry air to gradually win the convective battle. Did elect to nudge PoPs downward for the first period to account for the Cuban shadow influence. The caveat to this forecast is that if winds are able to go light and variable for a time this afternoon, developing cloud sterams across portions of the Lower and Middle Keys may coalesce into a broken cloud line feature. We will monitor this possibility over the next several hours. Besides the nudge down in PoPs across the Island Chain, no changes proposed to the inherited overnight package.

MARINE

Issued at 1111 AM EDT Thu Sep 3 2026 No watches, warnings, or advisories are currently in effect for the Florida Keys waters. From synopsis, the western periphery of a weak North Atlantic high will remain in loose control of the Keys coastal waters for the next several days. Light to gentle east to southeast breezes overnight through morning will become light and variable at times during the afternoon and evenings. In addition, the overall flow will keep low-level moisture in place across the region, with seasonally normal rain and thunder chances.

AVIATION

(15Z TAFS) Issued at 1111 AM EDT Thu Sep 3 2026 Although passing showers and thunderstorms cannot be ruled out, VFR conditions will prevail at both island terminals through 12z Friday morning. Near-surface winds out of the south to southwest may briefly become variable this afternoon,then will back to the southeast to south overnight.

PRELIMINARY POINT TEMPS/POPS

Key West 92 82 92 81 / 20 20 30 40 Marathon 90 83 90 82 / 20 30 30 40

KEY WATCHES/WARNINGS/ADVISORIES

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