textproduct: Key West

KEY MESSAGES

- Minor to moderate saltwater flooding of low elevation streets will continue through Friday morning. Don't drive through flooded roadways. Boaters can expect less clearance under fixed bridges.

- A Small Craft Advisory is in effect for the waters of the Florida Straits and southeastern Gulf, and Small Craft Should Exercise Caution in all other waters.

- A wet pattern will continue through Friday and Friday night. Rain and thunder chances will decrease over the weekend through early next week.

DISCUSSION

Issued at 1010 PM EDT Thu Oct 1 2026 Weather earlier today across the Florida Keys ended up being very busy. A heavy line of showers developed and moved north across the entire island chain after sunrise. Showers remained offshore until the afternoon. A backbuilding line of showers formed directly on top of Key West. Unofficial rainfall observations estimated a range of 3.5 to 5 inches of accumulation over the island with the heaviest rainfall closer to Old Town. The burst of heavy rainfall did prompt a Flood Advisory and a Flood Warning.

Shower coverage has decreased significantly across the Keys waters in the wake of these showers. The atmosphere was able to stabilize and a lull period is in effect for parts of the CWA. Heavier showers are still present over portions of the waters, but the island chain has, mercifully, been given time for water to recede. That does not mean the rounds of heavy rainfall are over. The evening 00Z KKEY sounding sampled an a PWAT only slightly below the record PWAT value for the day. Water vapor satellite observations from GOES East indicate the upper level trough, while moving slowly west, is still directing a significant amount of tropical moisture across the Keys. The subtropical ridge is still robust enough to sustain fresh breezes across the Straits of Florida. The synoptic features that allowed the sustained rounds of rainfall across the Keys remain in place.

For the rest of the night, expect a lull in shower coverage across the Keys. Convective models suggest showers could redevelop near the island chain before sunrise as early as 5 to 6 AM. In light of the widespread showers earlier today, we will be keeping the showers likely wording for the overnight. The biggest concern will be coastal flooding. Even though showers over the Keys ended before sunset, waters have taken a long time to recede. Light showers might cause minor to moderate saltwater flooding of low elevation streets and lots. Even though we are past the peak of the tide cycle, we are opting to keep the Coastal Flood Statement for the Middle and Lower Keys and the Coastal Flood Advisory for the Upper Keys. Watch the radar overnight and tomorrow, we have at least one more day of active weather.

MARINE

Issued at 1010 PM EDT Thu Oct 1 2026 A Small Craft Advisory is in effect for the Straits of Florida and southeastern Gulf. In the remaining marine zones, aside from Florida Bay, small craft should exercise caution for moderate to fresh breezes. Periods of showers and thunderstorms will move northwest at 15 to 20 knots, occasionally producing locally hazardous winds and seas.

From synopsis: high pressure offshore of the Eastern Seaboard will remain in place through Friday and into the weekend. This feature will maintain moderate to fresh southeasterly breezes across the Florida Keys waters through the overnight hours. Breezes are on track to slacken to moderate tomorrow. Southeasterly winds will continue to prevail this weekend with widespread moderate breezes on Saturday and subsiding to gentle to moderate on Sunday. The winds will remain southeasterly into early next week and generally remain less than 10 knots and seas 2 feet or less. In addition, a wet weather pattern will remain across the Keys marine zones overnight and tomorrow, resulting in periods of scattered to numerous showers and thunderstorms.

AVIATION

(00Z TAFS) Issued at 1010 PM EDT Thu Oct 1 2026 Prevailing VFR conditions at both EYW and MTH will be periodically interrupted by rounds of IFR CIGs and VISs related to heavy showers. SHRA are on track to redevelop near the island chain before sunrise, but confidence in where and when SHRA will reform is low. PROB30 wording is in place after sunrise. Winds are expected to start to decrease late tomorrow, and shower chances should wane near the end of the TAF period.

PRELIMINARY POINT TEMPS/POPS

Key West 80 90 81 90 / 60 50 40 40 Marathon 80 88 81 89 / 60 50 40 40

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Advisory until 6 AM EDT Friday for FLZ076.

GM...Small Craft Advisory until 6 AM EDT Friday for GMZ033-034- 052>055-072>075.