Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
381 FXUS62 KKEY 101415 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1015 AM EDT Sat Oct 10 2026 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... - A Coastal Flood Statement is in effect, and particularly low lying areas will see some saltwater ponding around the times of high tide. - Post-Tropical Cyclone Isaias has moved inland into southern Alabama after making landfall last night near Destin, FL. Residual westerly swell will continue this afternoon and evening across the western half of the coastal waters. - Elevated rain chances are expected beginning this afternoon, peaking tonight, before decreasing over the remainder of the holiday weekend. && .DISCUSSION... Issued at 1015 AM EDT Sat Oct 10 2026 Post-Tropical Cyclone Isaias has been absorbed into the mid- latitude winds. However, the effects of Isaias will continue to be felt through the first half of the weekend. Deep layers of moisture are surging across South Florida and the Keys. The morning 12Z KKEY sounding sampled a daily record maximum PWAT for the day. The challenge for this afternoon is what will happen with all this moisture. The sounding measured little to no instability in the environment, yet showers as observed by KBYX are struggling to form over the eastern waters of the Keys. Visible satellite observations do not see widespread cloud cover over the Keys. Mean layer winds observed by the sounding were near 20 knots, so the flow field is too strong to observe a Cuban shadow. Showers are able to form over the Outer Gulf, but have not been able to develop into thunderstorms. The thought is that as what used to be Isaias moves north, the pressure gradient will weaken and cause winds to slacken across the Keys. However, that would be the late afternoon to evening hours. This afternoon, expect gentle to moderate breezes across the Upper and Middle Keys while moderate to fresh breezes linger over the Lower Keys. Shower coverage is on track to remain surprisingly low, a slight chance to a chance, until the late afternoon. The problem is all the atmosphere needs is a bit of lift for showers to develop. Tonight, a building Atlantic High is expected to freshen winds over the eastern waters and thus provide that source of lift. Check back tonight because the environment is primed for rainfall. Finally, a Coastal Flood Statement remains in effect across the island chain. && .MARINE... Issued at 1015 AM EDT Sat Oct 10 2026 Small craft should exercise caution until winds decrease and seas subside for the westernmost waters of the Florida Keys. No other watches or warnings are in effect for the nearshore or offshore waters surrounding the Florida Keys. From synopsis: Post-Tropical Cyclone Isaias made landfall last night near Destin, FL. However, the lingering effects of the hurricane will be felt this afternoon and tonight. Moderate to fresh southeast to south breezes are expected to continue throughout the Florida Keys coastal waters, especially the SE Gulf, western Straits, and the nearshore waters surrounding the Lower Keys. Elevated swells will persist through the western FL Straits and the SE Gulf waters through tonight. Breezes will only modestly slacken to gentle to moderate as the cyclone continues to move away and ridging builds in behind it. The environment will remain primed for showers through Sunday before drying out during the start of the week. Afterwards, a frontal boundary associated with Post- Tropical Cyclone Isaias may push through the Florida Keys by mid- week. && .AVIATION... (12Z TAFS) Issued at 1015 AM EDT Sat Oct 10 2026 VFR conditions will prevail at EYW and MTH for the upcoming TAF period. Gusts are up and down across the Keys waters with increased shower coverage over the waters north of the terminals. Winds are expected to slacken after sunset, and shower coverage is on track to increase late in the period. && .CLIMATE... On this day on 2009, the daily record warm low temperature of 84F was recorded in Key West. Temperature records for Key West date back to 1872. Also, on this day in 1975, the daily record warm low temperature of 83F was recorded in Marathon. Temperature records for Marathon date back to 1951. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...AJP Aviation/Nowcasts....AJP Data Acquisition.....AJP Visit us on the web at weather.gov/key Follow us on Facebook and X at: www.facebook.com/nwskeywest www.x.com/nwskeywest