textproduct: Key West

KEY MESSAGES

- Major coastal flooding will continue over portions of the Upper Keys. Moderate coastal flooding in the Lower and Middle Keys may reach major levels as well as early as tomorrow night.

- A Gale Warning is in effect for all the Florida Keys coastal waters through Tuesday morning. - Fast-moving scattered showers will continue to move through the Keys through Tuesday night. Any of this activity will be capable of producing stronger wind gusts.

DISCUSSION

Issued at 200 PM EDT Mon Oct 26 2026 In terms of the sensible weather, there is quite the spread this afternoon across the Florida Keys. Portions of the Upper Keys, closest to a cyclonic disturbance centered south of the Bahamas, have remained mostly cloudy throughout much of the day, as fast- moving showers occasionally pass through. These showers have been generally shallow and light, with MRMS-derived rainfall estimates generally less than a tenth of an inch, even it some of the wetter locations. Meanwhile, in the Lower Keys, there has been very little in terms of shower activity, and the Middle Keys have served as a transitional zone for the rainfall. In the strong north to northeasterly gradient, temperatures continue to struggle to raise much above the morning lows, with most island communities hovering near 80F.

There is relatively good agreement among global ensemble numerical weather prediction guidance, supporting a relatively confidence forecast for the next several days. Very few changes were made relative to the inherited overnight forecast package. The aforementioned disturbance will very slowly lift northward in the west-central North Atlantic through Tuesday night. The system will continue to interact with a high pressure system centered near Virginia, that will then be reinforced by a second high north of the Great Lakes region. North to northeast windy conditions will continue, with breezes slowly slackening after Tuesday night, as the disturbance moves enough northward and the pressure gradient weakens. Forecast soundings also highlight decreasing tropospheric moisture for the middle to latter part of the week, and we continue to nudge to slight rain chances beyond mid-week. Highs should continue to hover near 80F through Tuesday, then modestly moderate for the latter part of the work week, as winds finally clock around to the northeast to east.

Outside of the windy conditions, the main weather story will continue to be coastal flooding concerns, with peak tides expected Tuesday night through Thursday night. Water levels in the Lower and Middle Keys will approach major flooding levels around the time of high tide, and the Coastal Flood Warning currently in the Upper Keys may need to be expanded. Peak water levels in the Lower and Middle Keys may approach six inches higher than experienced at around the time of high tide last evening. Although predicted tides will be on a downward trend after Thursday, it will be a slow process, with additional Coastal Flood Advisories likely needed through the weekend.

MARINE

Issued at 200 PM EDT Mon Oct 26 2026 Although we are experiencing a brief lull in wind speeds this afternoon, especially north of the Island Chain, breezes will once again freshen this evening and overnight. Frequent gusts will approach near gale levels for this period.

From synopsis, sprawling high pressure over the eastern United States will be reinforced by a secondary high north of the Great Lakes. As these features interact with a persistent low south of the Bahamas, this will sustain frequent near gale gusts this afternoon through Tuesday morning, especially across the Straits of Florida, extreme eastern Hawk Channel, and the SE Gulf waters. In addition, pulses of low level moisture will support elevated shower chances, mainly in the eastern marine zones. The secondary high will slide into the central North Atlantic for the middle to latter part of the work week, supporting slackening northeast to east breezes.

AVIATION

(18Z TAFS) Issued at 200 PM EDT Mon Oct 26 2026 Although VFR conditions will prevail at both TAF sites through 18z Tuesday afternoon, occasional MVFR ceilings will be possible, particularly near MTH. Activity in the eastern waters will slowly try to clip the terminals through the evening hours, when a window of VCSH is included in the TAFs. Impacts to visibilities will remain low. Near- surface winds will frequently gust to near 25 knots through 12z Tuesday afternoon, with any stronger shower possibly supporting gusts to near 30 knots.

PRELIMINARY POINT TEMPS/POPS

Key West 82 73 82 74 / 40 30 30 30 Marathon 81 73 81 74 / 40 40 40 40

KEY WATCHES/WARNINGS/ADVISORIES

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

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

GM...Gale Warning until 11 AM EDT Tuesday for GMZ031>035-042>044- 052>055-072>075.