Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
220 FXUS62 KKEY 060318 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1118 PM EDT Sat Sep 5 2026 ...New UPDATE, AVIATION... .KEY MESSAGES... - A moisture surge will support bouts of elevated rain and thunder chances through the Labor Day holiday weekend. - The primary threat for any stronger thunderstorms will be dangerous lightning strikes. When thunder roars, go indoors. If on a boat, stay low, or go below. - Heat indices will approach the mid 100s daily, with little relief in the muggy conditions overnight. Know the signs of heat stress, take frequent breaks, and stay hydrated. && .UPDATE... Issued at 1046 PM EDT Sat Sep 5 2026 The convection that occurred earlier this evening has mostly dissipated with recent KBYX imagery showing some light to moderate stratiform precipitation lingering across the Upper Keys. Given the rather pronounced near-surface stable layer evident in this evening`s KEY sounding, the expectation is that there should be less precipitation coverage across the region for the remainder of the evening and overnight hours, despite ample atmospheric moisture in place with PWATs in excess of 2" area-wide. That said, lingering boundaries from earlier convection and additional boundaries from lingering convection across the FL peninsula will still favor chance PoPs overnight with areas of scattered showers and isolated storms a possibility in any location. Meanwhile, surface high pressure drifts into the east central Gulf overnight with a larger surface high in the north Atlantic extending a ridge axis westward into the vicinity of the Keys, which will set up a light flow col pattern tonight into Sunday. Thus, a favorable pattern for cloud line development should be in place on Sunday with scattered storms expected along and near the Island Chain, possibly resulting in waterspout formation on occasion, in addition to other hazards such as gusty winds and lightning strikes. Otherwise, overnight lows will drop into the low 80s across the Island Chain with mostly cloudy skies given a fair amount of convective debris lingering across the region. && .MARINE... Issued at 1105 AM EDT Sat Sep 5 2026 No watches, warnings, or advisories are currently in effect for the Florida Keys. From synopsis, light to gentle southeast breezes will prevail through mid week as weak steering flow persists across the region, thereafter breezes will freshen to gentle to moderate as high pressure builds in. Waves of low- level moisture pushing across the Keys will support elevated rain and thunder chances through Sunday, possibly returning to near normal by mid week. && .AVIATION... (00Z TAFS) Issued at 1105 PM EDT Sat Sep 5 2026 VFR conditions will generally prevail through the overnight hours into Sunday with SE winds overnight becoming light/VRB tomorrow. However, scattered SHRA/TSRA may occur at times in the vicinity of either of the terminals across the Island Chain, which may result in brief MVFR/IFR impacts across the region, particularly during pockets of heavier precipitation. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...RG Aviation/Nowcasts....RG Data Acquisition.....RG Visit us on the web at weather.gov/key Follow us on Facebook and X at: www.facebook.com/nwskeywest www.x.com/nwskeywest