FXUS62 KKEY 040834 AFDKEY Area Forecast Discussion National Weather Service Key West FL 434 AM EDT Mon May 4 2026 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... - A few large clusters of showers with embedded thunderstorms will gradually taper off today. Rain chances will remain slightly above normal tonight, but any activity should be considerably weaker. - Light to gentle variable breezes this morning will gradually become broadly northerly today, and northeasterly tonight. Expect periods of variability until light to gentle east to southeasterly breezes build in by mid week. - Rain chances become slim to none by mid week, and continue through most of the remainder of the week. && .DISCUSSION... Issued at 430 AM EDT Mon May 4 2026 A weakening frontal boundary is slowly working its way southward into the Florida Straits this morning. In response, light breezes along the island chain have finally shifted to the long expected northwesterly direction. This shift, along with convective outflows has lowered dew points in most locations to the a degree or two above 70. Temperatures now range from the upper 70s in the Lower Keys to the lower 70s in the Middle and Upper Keys. Meanwhile, a mid latitude trough over the eastern United States and a phasing shortwave trough moving across Florida has contributed to a good amount of diffluent flow aloft. After several rounds of showers and thunderstorms across the Forecast area, the strongest activity is now focused across the Florida Straits. With that said, a large swath of light to moderate rain continues to blanket the Middle and Upper Keys. For today, precipitable water will remain near or slightly above the 90th percentile with nearly saturated lower levels and modest CAPE. The shortwave trough aloft will lift out into the Atlantic, leaving a broad synoptic trough that reaches into the northwestern Caribbean Sea. Rain and thunder activity will ease back considerably today due to the above and as the surface boundary creeps more fully into the Florida Straits turning further north. With that said, rain chances will remain above normal due to the lingering copious low level moisture, moderately unstable atmosphere, and weakening support, both aloft and through the lower levels. Temperatures will be near normal with dew points remaining in the lower 70s. The mid latitude trough will push east of our area tonight, and a strengthening mid to upper level ridge will drive eastward into the Gulf of America on Tuesday. In addition, a surface Atlantic ridge will become better established across Florida tonight into Tuesday and slowly wash out the lingering troughing across the Florida Straits. Until then, light surface breezes will quite often be variable, then become prevailing light east to southeasterly by mid week. As this transition occurs, precipitable water will drop to slightly below normal with increasing lower level inhibition. Expect rain chances to fall out of the forecast by mid week. Temperatures will be near normal until the east to southeasterlies start bringing in warmer and more humid air. Temperatures will climb into the upper 80s for the high and upper 70s to near 80 for the low. Dew points will return to a muggy mid 70s. && .MARINE... Issued at 430 AM EDT Mon May 4 2026 Light to gentle southerly breezes will shift clockwise, becoming broadly northerly today as a weak frontal boundary sags south of the Keys this morning. A few showers and thunderstorms may be strong, and produce strong gusty breezes, and at times, frequent lightning strikes. The wet pattern will slowly dissipate over the next 24 hours as high pressure pushes south across Florida. Rain and thunderstorm chances will trend down to seasonal norms by Tuesday and below normal by mid week. Breezes will eventually become a closer to normal light to gentle east to southeasterlies. Wind direction may be poorly defined at times until the ridge becomes better established on wednesday. && .AVIATION... (00Z TAFS) Issued at 430 AM EDT Mon May 4 2026 The wet pattern affecting the Keys will gradually diminish today. There will still be a mid to high chance for showers with embedded thunderstorms. Aside from showers and thunderstorms, VFR conditions will prevail. Surface winds will be highly contaminated by convection. In general, winds will be light to gentle out of the north. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...11 Aviation/Nowcasts....AJP Data Acquisition.....AJP Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest