textproduct: Key West

KEY MESSAGES

- Minor to moderate saltwater flooding of low elevation streets and lots is likely to continue over the next few day or so due to King Tide. Don't drive through flooded roadways. Boaters can expect less clearance under fixed bridges.

- A Coastal Flood Advisory is in effect for all of the Florida Keys.

- A wet pattern is expected for the next several days across the Keys. This will maintain above normal rain and thunder chances through at least Thursday.

DISCUSSION

Issued at 417 AM EDT Wed Sep 30 2026

The Florida Keys are in a momentary lull with the KBYX radar surprisingly quiet all across our CWA. Nearest area of convection is moving off the north coast of Cuba and beginning to enter open waters. Time will tell if this activity lingers into our waters. Otherwise, we are in the thick of it so to speak. An upper level trough lies to our west across the central Gulf Basin, extending well into the Yucatan Peninsula. This has placed the Keys under a deep southerly flow that continues to transport tropical moisture from the western Caribbean. In fact, we're monitoring the nearly west to east line of convection that has been steadily moving north and is currently reaching Cuba. This line is on pace to reach the Keys between 0900-1200 today. Given this trajectory plus the deep tropical moisture influx and the presence of the nearby upper level trough, likely PoPs can be expected today. In addition, we continue to be under the influence of King Tides, therefore, should heavy rain coincide with times of high tide, we could see brief periods of enhanced flooding.

Meanwhile, to our north, a surface high pressure sits along the Eastern Seaboard. This feature will slowly meander offshore throughout the day and merge with an existing Atlantic Ridge and subsequently build. This will lead to freshening east to southeast breezes across the region. It is becoming increasingly likely that we will see a period of breezy conditions with marine Caution headlines likely across the surrounding coastal waters. There is a chance that given the early nature of this building high that models may be slightly underplaying the strength of the winds. Nonetheless, we can expect a period of moderate to fresh breezes at least through Friday. Thereafter, the ridge will gradually ease and allow for breezes to slowly slacken back to gentle to occasionally moderate over the weekend. As the high eases, we should see rain chances return closer to normal for what will be the first weekend of October.

MARINE

Issued at 417 AM EDT Wed Sep 30 2026

Gentle to occasional moderate east to southeast breezes have returned after a period of active weather last evening and early in the overnight. Breezes will gradually freshen through the day as a high pressure currently along the Eastern Seaboard moves offshore and merges with an existing Atlantic Ridge. There is growing confidence of moderate to fresh breezes developing tonight. There is low confidence, however, that we will reach Small Craft Advisory threshold winds. For now if we were to see them, they would be in the Straits of Florida. Moderate to occasionally fresh breezes will linger through at least Friday before slackening into the upcoming weekend. Active wet pattern will persist through at least Thursday with above normal rain/thunder chances.

AVIATION

(06Z TAFS) Issued at 417 AM EDT Wed Sep 30 2026

The atmosphere is currently worked over from earlier convection and as such, we anticipate a continued break from the active weather for at least the next 6 hours. The next round of convection is passing over the island of Cuba and is progged to reach the island chain around or after 14Z. Have maintained a PROB30 for TSRA during this period.

PRELIMINARY POINT TEMPS/POPS

Key West 88 78 89 79 / 70 80 80 60 Marathon 87 79 88 80 / 70 80 70 50

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Advisory for FLZ076>078.

GM...None.