Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
279 FXUS62 KKEY 240825 AFDKEY Area Forecast Discussion National Weather Service Key West FL 425 AM EDT Tue Jun 24 2025 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 430 AM EDT Tue Jun 24 2025 A push of very dry air in the mean low- and mid-level easterlies was detected in the 00z evening sounding at KEY, particularly in the 600-800 mb isobaric layer. This largely has limited shower and thunderstorm activity so far overnight. With that being said, CIMSS satellite- derived total precipitable water product is highlighting somewhat more moist air upstream in the vicinity of the islands of the Bahamas. Over the past hour or so, KBYX Doppler radar has highlighted somewhat larger isolated shower activity over the Florida Keys marine zones associated with the likely middle troposphere moistening (along with the diurnally- favored overnight period for enhanced shower activity), although most island communities have remained dry. Surface observations indicate temperatures in the lower to mid 80s at this hour, with dew points in the seasonally muggy lower to mid 70s. Composite satellite vorticity analysis places a weak low-level tropical wave now currently approaching Hispaniola, as well as a surface low-pressure system to the northeast to east of Bermuda. Meanwhile, further aloft, a mid- and upper-level low pressure system is situated further to the southwest. Global ensemble mean fields have the upper-level low retrograding southwestward over the next 48-72 hours, eventually parking in the vicinity of the Florida Peninsula. The wave axis associated with the lower-level disturbance near the Antilles will push towards the Straits of Florida roughly during the same time period. All said, enhanced shower and thunderstorm chances expected for Wednesday night through Thursday night. Thereafter, NASA dust aerosol optical thickness forecasts show another push of Saharan dust towards the Keys, when much lower rain and thunder chances are expected by late Friday through the weekend. Outside of any brief windows of rain-cooled temperatures across some of the Florida Keys islands, ample breaks in cloud coverage and shower activity should still allow high temperatures to reach well into the upper 80s for the next seven days, with seasonably warm lows in the lower 80s. && .MARINE... Issued at 430 AM EDT Tue Jun 24 2025 Small Craft Should Exercise Caution headlines are posted for the Straits of Florida. Otherwise, there are no watches, warnings, or advisories currently in effect for the Keys coastal waters. From synopsis, high pressure will remain dominant over the Florida Keys coastal waters through Wednesday, allowing for mainly gentle to moderate easterly breezes. A tropical wave will approach the Keys late Wednesday and Thursday. This feature, in tandem with a retrograding upper-level low moving southwestward towards the Florida Peninsula, will support enhanced rain and thunder chances for Wednesday night through Thursday night. Gentle to moderate east to southeast breezes, along with drier conditions, are expected for late Friday through the weekend. && .AVIATION... (06Z TAFS) Issued at 430 AM EDT Tue Jun 24 2025 VFR conditions will prevail at EYW and MTH through the TAF period, although brief transient bouts of MVFR CIGs are possible as a chance of passing showers and thunderstorms remains. Areal coverage and timing of any showers that occur are too uncertain to include in the TAFs at this time and will be covered by amendments and later routine TAFs as needed. Winds will continue to be from the east at 10 to 15 knots, with gusts to near 20 knots. && .CLIMATE... On this day in 2023, the daily record high temperature of 94F and the daily record warm low temperature of 85F were recorded at Marathon. Temperature records for Marathon date back to 1950. && .PRELIMINARY POINT TEMPS/POPS... Key West 89 80 88 80 / 30 30 40 40 Marathon 88 80 88 80 / 30 30 40 40 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...BT 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