textproduct: Key West

KEY MESSAGES

- Major coastal flooding in the Upper Keys and minor to moderate coastal flooding in the Lower to Middle Keys is ongoing, especially around high tide.

- Small Craft Advisory conditions are expected from tonight through early next week. Near-gale breezes will be possible at times Sunday evening through Monday evening. - Little to any relief in significant coastal and marine impacts are expected into at least the middle of next week. Residents and visitors should take the necessary actions to protect flood- prone property.

DISCUSSION

Issued at 942 PM EDT Fri Oct 23 2026 Shower and thunderstorm activity has expanded across the area over the last hour or two. We're situated just downstream of a mid to upper-level trough axis which extends north along the Eastern Seaboard into the North Atlantic. GOES-E vorticity products show strong mid to upper-level PVA occurring across the area with little to no reflection in the lower levels. Up to this point, the atmosphere has remained largely capped by a subsidence inversion beginning around 780mb. The 00Z KKEY RAOB indicates that this inversion is perhaps less restrictive this evening due to warmer surface temperatures. This corraborates the uptick in development across our warm waters which is also gaining some assistance from land breeze activity surging southwest from the Florida mainland. As boundaries propogate south across the island chain, precip chances should remain highest in the Straits of Florida through the remainder of the night. This is preferred as we certainly don't want heavy rain to compound with ongoing King Tide coastal flooding. The trough axis will continue to slowly shift eastward tonight which will focus most of the synoptic scale lift to our east and place us somewhat on the drier side of the trough tomorrow. Northeast winds are also beginning to freshen with several marine observations reporting 15-20 kt sustained winds in the nearshore waters. Expect winds to continue growing stronger through tomorrow morning as the strong surface ridge builds over the Eastern CONUS, promoting an intensifying gradient as it interacts with surface troughing near and just east of the Bahamas.

MARINE

Issued at 942 PM EDT Fri Oct 23 2026 A Small Craft Advisory is in effect for all Florida Keys marine zones. Scattered showers and thunderstorms will continue to propogate towards the south-southwest around 5 to 10 knots through tonight, mainly in the Straits of Florida. Northeasterly breezes are beginning to freshen with several marine observation sites reporting sustained winds of 15-20 knots.

From synopsis, high pressure centered just north of the Great Lakes region will continue to slide eastward and strengthen over the next several days. As this occurs, the high will interact with a developing disturbance in the eastern Caribbean, supporting freshening northeasterly breezes over the next several days. Breezes will peak Sunday night through Tuesday, when strong to near gale breezes will be possible. The freshening breezes and a surge of moisture may also support elevated rain and isolated strong thunderstorm chances Friday night through Monday.

AVIATION

(00Z TAFS) Issued at 732 PM EDT Fri Oct 23 2026 Scattered showers and isolated thunderstorms are tracking southwest near the terminals along a mainland Florida land breeze. This activity will likely miss the terminals, but will remain in the vicinity until around 06Z with VFR expected to continue thereafter. Northeasterly winds will also increase around 06Z with gusts of 20-22 kts.

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Warning until 5 AM EDT Saturday for FLZ076.

Coastal Flood Advisory until 5 AM EDT Saturday for FLZ077-078.

GM...Small Craft Advisory until 8 PM EDT Monday for GMZ031>035- 042>044-052>055-072>075.