Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
761 FXUS62 KKEY 030707 AFDKEY Area Forecast Discussion National Weather Service Key West FL 307 AM EDT Thu Jul 3 2025 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 307 AM EDT Thu Jul 3 2025 A TUTT cell north of the Bahamas is dissipating and being absorbed into the upper level flow. Meanwhile, an upper level trough axis that has been slowly moving across the Southeast U.S and across the Florida Peninsula, now lies to our northwest. At the surface this has resulted in a fractured high pressure that extends across the Atlantic and into the Gulf basin. This has left the Keys in a col region with an axis of dilatation across the Lower Keys. To the east of this axis, surface winds are from the southeast and south, while to the west they are west to northwest. Along this axis some weak showers have developed and are trekking northeast. While last evenings sounding showed quite a bit of moisture, we lack any large scale robust lift and as such, the shower activity is meager this morning. The Florida Keys lie right on the boundary between the residual SAL and the incoming moisture plume from the upper level trough. With that said, the majority of the Keys will stay on the SAL side of things and rain chances will remain limited. Across the deep Gulf waters, where moisture has been pooling, is where most of the activity will occur. This slowly changes over the next 24 hours as the upper level trough makes its closet approach to the island chain. That being said, the best moisture and lift will stay to our north. As a result, rain chances will gradually increase to low end chance (30 percent) tonight, and further increasing to high- end chance (50 percent) Friday. Rain chances will remain elevated through the first half of the weekend. Rainfall amounts with this system look to be generally less than 1 inch across the next several days with locally higher amounts possible. The upper level trough will eventually get picked up by the main flow and lift northeast away from the Sunshine State. As it does, the moisture will be gradually pulled with it. Rain chances will decrease Sunday and continue into early next week. In addition, as the upper level disturbance exits, the low level ridge will nose back in from the east. This will result in a return of easterlies as well as the occasional moisture surge. Therefore, rain chances will hover generally near normal through the majority of the week. && .MARINE... Issued at 307 AM EDT Thu Jul 3 2025 Broad low-level ridging will continue to rebuild over the North Atlantic. This will initially support light to gentle southeast to south breezes across Florida Keys coastal waters and gradually clock around to the southwest and west as trough of low pressure approaches the region from the north. Rain chances will increase by Friday and remain elevated through Saturday evening as a result. As the trough exits the region and lifts northeast starting Sunday, a weak ridge axis will lie across the Florida Keys, resulting in generally light to gentle easterly breezes. && .AVIATION... (06Z TAFS) Issued at 307 AM EDT Thu Jul 3 2025 VFR conditions are expected to prevail at the terminals through the TAF period, though brief transient episodes of MVFR CIGs are possible as sky coverage waxes and wanes. Some showers and isolated thunder are possible, particularly during the daytime hours, but chances remain low and coverage and timing uncertain, so refraining from inclusion in the TAF for the moment. Winds are expected to remain generally from the south at 5 to 10 knots, but could become light and variable at times, particularly in the afternoon. && .TROPICAL... An area of low pressure is forecast to develop along a weakening frontal boundary near Florida or the Atlantic coast of the southeastern United States by early this weekend. Environmental conditions appear only marginally conducive for some slow development, but a tropical or subtropical depression could form in this region over the weekend or early next week while the system drifts northward or northeastward. Regardless of development, heavy rainfall is possible across portions of the southeast U.S., particularly across the west-central Florida coast. Regardless of development, there are no major concerns for the Florida Keys at this time. && .CLIMATE... On this day in 2023, the daily record high temperature of 96F was recorded at Key West. Temperature records for Key West date back to 1872. && .PRELIMINARY POINT TEMPS/POPS... Key West 90 81 90 81 / 20 30 50 50 Marathon 88 80 88 80 / 20 20 50 50 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...LIW 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