Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
133 FXUS62 KKEY 140821 AFDKEY Area Forecast Discussion National Weather Service Key West FL 421 AM EDT Tue Oct 14 2025 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... -Slight rain chances expected for the next several days as dry air dominates the Florida Keys. -Humidity levels will be below normal through most of the week. -A Coastal Flood Statement remains in effect for the Lower and Middle Keys. -A Coastal Flood Advisory remains in effect for the Upper Florida Keys. Little relief in coastal flooding is expected, even outside the times of high tide. -Tropical Storm Lorenzo, located in the central Atlantic, will not be a threat to the Keys. && .DISCUSSION... Issued at 421 AM EDT Tue Oct 14 2025 A deep upper level trough across the eastern United States, south to the Florida Peninsula, will begin to move offshore today and tonight. Resulting conditions over the Florida Keys will be a bit complicated. Advected Layer Precipitable Water products from polar satellite passes detect low amounts of moisture in the upper atmosphere, but the surface to 700 layers remain moist. Nighttime microphysics observations from GOES-East show patchy low to mid level cloud cover, mostly over the Florida Straits, and the KBYX radar indicates showers are still pulsing south of the island chain. Breezes are the concern for the day, because marine platforms along the reef are measuring fresh breezes this morning. Temperatures are slightly moderated, and lows in the upper 70s are expected before sunrise, so long as the low level cloud ceilings break up. All in all, conditions for the day are expected to be uneventful along the island chain, so long as you are staying on land. Also, remember that a Coastal Flood Advisory is out for the Upper Keys, and a Coastal Flood Statement is in effect for the Middle and Lower Keys. Avoid flooded roads where possible! .FORECAST... The forecast challenge for the upcoming week will be placing the precipitable water gradient between Florida and Cuba. The upper level pattern is shifting to allow sinking air over the southeastern CONUS, but moisture transport north of Cuba will cancel out some of the subsidence. The current forecast shows more subsidence, and thus drier conditions, through midweek. The pattern shifts by the end of the week, and the subsident pattern shifts eastward into the Atlantic. Near normal (around 20%) to above normal rain chances return over the weekend as the wind pattern shifts from northeasterlies to east-southeasterlies in the lower atmosphere. Breezes will be the other topic of interest. When the upper level trough moves offshore, a mid latitude low is expected to develop off the Eastern Seaboard. At the same time, a high pressure system along the Canadian border will sink southeast over the Great Lakes. Slackening breezes are expected midweek before the high sinks south towards the Carolina coastline. Once the high set up over the southeastern US, fresh breezes are possible across the Keys waters this weekend. Small Craft Advisories are possible depending on the southward extent of the high and the location of the pressure gradient. The windy season is fast approaching, so check back later for an update on whether or not boating will be seasickness inducing across the Keys. && .MARINE... Issued at 421 AM EDT Tue Oct 14 2025 There are currently no watches, warnings, or advisories in effect for the Florida Keys coastal waters. Small Craft Should Exercise Caution for the Atlantic-side waters, and Small Craft Should Exercise Caution Until Winds Decrease for gulfside waters, except for Florida Bay. From synopsis, a low pressure system developing off the eastern seaboard and a high pressure system over the eastern United States will allow moderate to fresh breezes today and tonight. Slackening winds are expected on Wednesday as the aforementioned low moves east. By the end of the week, high pressure will set up along the Carolina coast and support freshening breezes. Expect peak breezes during the late evening to mornings, and lulls in the afternoons. Shower coverage will remain isolated to scattered. && .AVIATION... (06Z TAFS) Issued at 421 AM EDT Tue Oct 14 2025 Scattered showers persisting regionally early this morning warrant inclusion of VCSH in the TAFs for the moment. However, timing and duration of passage of these showers precludes inclusion of any sub- VFR categorical details at this time. These impacts will be addressed via amendment if needed. Outside of these showers, VFR conditions are expected to prevail throughout the TAF period. Northeast winds 5 to 10 knots persist through the period, with gusts up to 20 knots beginning midday. && .CLIMATE... On this day in 1964, category 3 Hurricane Isbell moved northeast off of the western tip of Cuba, passing just west of the Marquesas Keys and northwest of the Keys. In Key West, the minimum pressure was 29.49 inches and the peak wind was 73 mph with a 4-5 ft tide. && .PRELIMINARY POINT TEMPS/POPS... Key West 87 76 86 76 / 20 10 10 10 Marathon 86 76 84 75 / 20 10 10 10 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...Coastal Flood Advisory until 5 AM EDT Wednesday for FLZ076. GM...None. && $$ Public/Marine/Fire...AJP Aviation/Nowcasts....MC Data Acquisition.....MC Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest