Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
617 FXUS62 KKEY 230231 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1031 PM EDT Tue Sep 22 2026 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... - There is a marginal risk for excessive rainfall through Thursday morning as topical moisture spreads into the area over the next several days. - Drier air associated with a cold front will arrive late week and into the weekend and will bring a lower risk of excessive rainfall, though some rain chances will linger. - Increasing northeasterly swell in the wake of the cold front will allow seas to build up to 5 feet by the end of the week and into the weekend, especially in the easternmost Straits of Florida. && .DISCUSSION... Issued at 907 PM EDT Tue Sep 22 2026 A wetter than normal pattern remains anchored across our area this evening. At the upper levels, an amplified trough reaches southward across the eastern Gulf and into the Yucatan. Meanwhile, weak surface through lower level troughing is found below this, stretching northeastward from the southern Gulf, through the Florida Peninsula, and off the Atlantic Coast. This has resulted in a broad swath of very high moisture remaining across our area along with periodic rounds of higher than normal activity. This evenings sounding indicated 2.36 inches of precipitable water, not far off from the daily maximum. CAPE was modest with nearly no cap. Overall activity has been picking up steadily through the evening, with the Upper Keys being the recipient of most of the activity so far. The wet pattern will continue through the overnight period as the respective upper and lower level troughs remain in place, essentially unchanged. This will keep the lower levels moist and weakly confluent and weak upper level diffluence across the broader area. Will maintain likely PoPs for the overnight period. Expect surface winds to remain light out of the southeast to south. Overnight lows will be in the upper 70s to near 80 with dew points in the mid 70s. && .MARINE... Issued at 907 PM EDT Tue Sep 22 2026 Weak surface troughing centered in the Gulf of America is resulting in light southeasterly breezes on Keys waters this evening. Expect light breezes to shift west of south overnight as the trough extends northeastward into the Florida Peninsula. A wet pattern remains in place across our waters. As a result, expect bouts of higher shower and thunderstorm coverage. && .AVIATION... (00Z TAFS) Issued at 907 PM EDT Tue Sep 22 2026 A wet pattern remains across the Keys this evening. As a result, periods of sub VFR conditions are possible at the island terminals overnight. Surface winds will be light out of the southeast to south. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...11 Aviation/Nowcasts....11 Data Acquisition.....DP Visit us on the web at weather.gov/key Follow us on Facebook and X at: www.facebook.com/nwskeywest www.x.com/nwskeywest