textproduct: Key West

KEY MESSAGES

- Saltwater flooding of low elevation streets and lots is likely through next week due to a potent King Tide. Don't drive through flooded roadways. Boaters can expect less clearance under fixed bridges.

- A Coastal Flood Statement is in effect for the Florida Keys. Coastal Flood Advisories may be required as early as Sunday night, and will likely be required for much of the Keys by Monday night.

- Increasing northeasterly swell from a Nor'easter off the East Coast will allow seas to build to 4 to 5 feet through the weekend in the eastern Straits of Florida off the Upper Keys.

DISCUSSION

Issued at 1115 AM EDT Fri Sep 25 2026 Surface and radar analysis highlights an early-season cold front that pushed through the Florida Keys earlier today now slowly progressing southward in the Straits of Florida. Convection continues in the best zone of surface confluence, mainly in the western Straits of Florida south of the Dry Tortugas. GOES-19 visible satellite imagery shows a broken deck of low stratus in the wake of the front slowly breaking up, yielding partly cloudy skies across the Florida Keys. Surface observations also indicate the moisture gradient associated with the front is lagging behind the frontal passage, but not far away. The most recent observation from Naples, FL sampled a 70F dew point.

For the balance of today, breezes will continue to decrease. Most island communities will remain rain-free. The exception to this will be in a zone of modest confluence over the South Florida Mainland. Any developing showers could clip portions of the Upper Keys later this afternoon or evening. The main weather story this weekend will continue to be elevated tides. A strengthening early-season Nor'easter off the coast of the Mid Atlantic will support a back up of our Gulf Stream. Combined with peaking King Tides, an extended period of minor flooding is expected, possibly peaking near moderate levels Sunday through Tuesday. The forecast remains on track, with no changes proposed.

MARINE

Issued at 1115 AM EDT Fri Sep 25 2026 Any remaining scattered showers and thunderstorms will gradually wane across the Straits of Florida over the next several hours. Tides will continue to build over the weekend, peaking Sunday through Tuesday. Boaters can expect less clearance under fixed bridges, especially around the time of high tide.

From synopsis, an early season cold front will continue to push southward through the Straits of Florida this afternoon. Gentle to moderate north to northeast breezes will gradually slacken in the wake of the front, becoming light to gentle over the weekend. A Nor'easter off the Eastern Seaboard will support a northeasterly swell in the eastern marine zones through Sunday. The front will push back northward late Sunday night through the marine zones. Winds will then clock back around to the southeast for early next week, also accompanied by increasing rain and thunder chances.

AVIATION

(12Z TAFS) Issued at 1115 AM EDT Fri Sep 25 2026 Bouts of MVFR ceilings in the wake of a cold front will continue to be possible over the next couple of hours in the vicinity of the terminals. Have included a TEMPO group to account for this, with periods of sub-VFR ceilings gradually diminishing by 18z. Near-surface winds generally out of the north will slowly wane, with gusts becoming much less frequent also after 18z this afternoon.

PRELIMINARY POINT TEMPS/POPS

Key West 88 77 87 77 / 10 10 10 10 Marathon 86 77 86 77 / 10 20 10 10

KEY WATCHES/WARNINGS/ADVISORIES

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