Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
665 FXUS62 KKEY 040930 AFDKEY Area Forecast Discussion National Weather Service Key West FL 430 AM EST Tue Nov 4 2025 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... -Strong high pressure over southern Appalachia will result in moderate to fresh mainly northeast breezes continuing through at least this evening for the Island Chain. -A Small Craft Advisory is in effect for most Keys waters today. Winds are expected to remain a bit weaker on Gulf and Bay waters adjacent to the Middle and Upper Keys, where only cautions remain advertised. -Breezes will slacken mid to late week as high pressure over the southeast pushes out onto the Atlantic and a trough swings through the eastern United States. && .DISCUSSION... Issued at 426 AM EST Tue Nov 4 2025 GOES East Total Precipitable Water (TPW) products shows the Keys in the squeeze play zone. There is higher moisture off to the southeast mainly across the Straits and out to the Bahamas. PWAT values here are being estimated to be between 1.5 to 1.8 inches. Closer to the Island Chain and to the north, the PWAT values are lower between 1.3 to 1.5 inches. This is making for a decent gradient in regards to the moisture across the area. KBYX radar has been detecting showers all night mainly across the Straits of Florida, especially since this is where the deeper moisture has remained overnight. This activity has been generally moving in a northeast to southwest fashion. In the past hour, lightning was observed right at the border of the Keys forecast area across the southern distant Straits of Florida due south of Woods Wall East Crack. GOES East Nighttime Microphysics shows mostly mid to high level clouds streaming from south to north across the Keys resulting in partly cloudy skies. Temperatures along the Island Chain are in the mid 70s with dew points in the upper 60s to near 70 degrees. In the wake of the cold front last evening, breezy conditions have developed along the Island Chain with Key West and Marathon gusting between 19 to 23 mph over the last few hours. In addition, marine platforms surrounding the Keys have been observing moderate to fresh north to northeast breezes. .FORECAST... Strong high pressure currently centered over the southern Appalachians will continue to slowly traverse to the east through early Wednesday. This high will move offshore sometime Wednesday. As it does so, it will flatten and weaken as it continues moving farther out into the western North Atlantic as we head into late week. This will promote breezy conditions continuing through this evening for the Island Chain with the marine area holding onto the stronger breezes until at least early Wednesday morning. Breezes will continue to slacken to mostly gentle to moderate for late week as another high moves across the eastern United States, albeit, weaker than the current one. Breezes will peak at night into the morning and then most likely lull in the afternoons. As the high continues moving out to sea over the weekend, expect further slackening breezes to light to gentle. Moisture is largely expected to remain across the Straits on south for today through Wednesday keeping rain chances out of the forecast till Wednesday night. Slight moisture return Wednesday night results in slight chances of rain creeping back into the forecast. This moisture will become a little bit deeper late week into the weekend resulting in rain chances ticking up slightly more (~20%). Humidity will also start to increase again late week and especially over the weekend. Model guidance remains in reasonably good agreement outside of timing for a potentially potent cold front early next week. What we know right now is expect another increase in winds leading to another potentially breezier period, cooler temperatures, and significant dip in dew points (humidity). Stay tuned as this could be a fairly significant blow out of the north to northeast for the Florida Keys coastal waters. && .MARINE... Issued at 426 AM EST Tue Nov 4 2025 A Small Craft Advisory remains in effect across most of the Florida Keys coastal waters. The exception being Florida Bay and the Bayside/Gulfside waters to the north of the Middle Keys. Small Craft Should Exercise Caution (SCEC) remains headlined for Florida Bay and the Bayside and Gulfside waters. From synopsis, in the wake of the front, strong surface high pressure will slowly migrate eastward across the Southeast U.S. and maintain moderate to fresh breezes through early Wednesday. Thereafter, breezes slacken as the ridge moves out into the Atlantic and weakens. && .AVIATION... (06Z TAFS) Issued at 426 AM EST Tue Nov 4 2025 VFR conditions will prevail at both EYW and MTH through the TAF period. Breezy northeast winds will continue through the afternoon, then slacken towards sunset. A mid to high deck of clouds will linger throughout much of the day but will not create any impacts && .CLIMATE... In 1966, the daily record low temperature of 57F was recorded in Key West. Temperature records date back to 1872. This day in history has several events of note... In 1998, the outer rainbands of Tropical Storm Mitch produced an F1 tornado which did $100k damage in Islamorada, an F0 tornado producing $50k damage in Rock Harbor, and an F2 tornado which did $25.0m damage and caused 20 injuries in Key Largo. In 1935, a weakening Hurricane moved west southwest over extreme South Florida and about 35 miles north of Key West, where a minimum pressure of 29.68" and a peak wind of 36 (units unknown) were recorded. In 2022, a waterspout outbreak occurred near the westernmost Lower Keys from 1658-1808L, with a family of 12 waterspouts observed. The first two were reported about 6 miles south of Boca Chica at 1658L and additional ones continued forming along a cloud line that extended southwestward to about 28 miles SW of Key West. The widest waterspout formed along a kink in the cloud line where it shifted more WSW. This spout was estimated to be a couple of hundred feet wide, lasted over 30 minutes, and the condensation cloud extended about a third of the way from the cloud base to the surface. Most of the other condensation clouds only extended a quarter of the way from cloud base to the horizon. Two additional waterspouts were observed north of Key West between 1836-1846L, also with the condensation cloud only extending a quarter of the way down from the cloud base... bringing the total for the afternoon/evening to 14 waterspouts. && .PRELIMINARY POINT TEMPS/POPS... Key West 80 75 81 75 / 10 10 10 10 Marathon 80 74 82 74 / 10 10 10 10 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...Small Craft Advisory until 5 PM EST this afternoon for GMZ033>035-042>044-052>055-072>075. && $$ Public/Marine/Fire...MJV Aviation/Nowcasts....LIW Data Acquisition.....LIW Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest