Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
073 FXUS62 KKEY 200756 AFDKEY Area Forecast Discussion National Weather Service Key West FL 356 AM EDT Thu Jun 20 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 355 AM EDT Thu Jun 20 2024 A much quieter and more tame overnight for the Florida Keys. This comes as somewhat of a surprise. This is despite the Keys lying on the eastern edge of a mid level cut-off low that is sliding west southwest, which puts us in a more favorable region. Unfortunately this is being counteracted by a relatively deep layer of dry air just above the boundary layer. This is inhibiting not only shower development but also vertical growth. With that, as of writing this, there is a cluster of showers and thunderstorms that has moved off the coast of Cuba and is pivoting northwest towards our waters. Time will tell if the dry air makes quick work of this cluster. Lastly, Tropical Storm Alberto continues to make westward progress towards Mexico and is expected to make landfall in the next few hours. .FORECAST... An easterly undulation is currently centered northeast of the Bahamas will trek west northwest today. The dry air out ahead of this feature has driven down PoPs for today, despite favorable mid level support. Therefore took PoPs down to 30 to 40 percent for today, with the best chances possibly favoring the Lower Keys, especially Stock Island and west. Here the moisture and lift will be the "best" and I use that loosely given how lackluster the overnight activity has been. As the undulation move inland across the Southeast U.S., better moisture should return behind this feature. This is generally supported by both the GFS and ECMWF although the GFS is more aggressive with the moisture return. Friday through Sunday, ridging will build equatorward across the western North Atlantic, maintaining a moist, easterly flow. Therefore, have stayed the course with middle of the road PoPs with the caveat that there will be a day that is wetter than the rest this weekend, but confidence on which day is low. Beyond Sunday, a new new continental ridge will slide through bringing with it a more northerly flow aloft. This should bring with it a relatively drier air mass and PoPs will return closer to normal next week. && .MARINE... Issued at 355 AM EDT Thu Jun 20 2024 Small Craft Advisories remain in effect for all of the Florida Keys coastal waters due to fresh easterly breezes. Strong high pressure centered north of Bermuda working in tandem with Tropical Storm Alberto near the Bay of Campeche will result in moderate to fresh breezes today and this evening. A second, weak area of low pressure currently north of the Lesser Antilles will move west northwest reaching the southeast U.S by late this evening or overnight. This, along with weakening Alberto over Mexico, will loosen the pressure gradient, leading to slackening east to southeast breezes for Friday through the first part of next week. && .AVIATION... (06Z TAFS) Issued at 355 AM EDT Thu Jun 20 2024 VFR conditions will prevail at both EYW and MTH through the TAF period. The morning and early afternoon hours should remain free of any activity, but VCSH have been added to the TAFs to include the timeframe from 20Z and onward. TEMPO groups may need to be added later today if robust activity looks to impact either airfield. && .CLIMATE... On this date in 1983, an F1 tornado produced $2.5m in damage near Lower Sugarloaf Key. There were no tropical cyclones in the area. && .PRELIMINARY POINT TEMPS/POPS... Key West 88 80 89 81 / 40 40 40 50 Marathon 88 81 89 82 / 30 30 40 50 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...Small Craft Advisory for GMZ031>035-042>044-052>055-072>075. && $$ Public/Marine/Fire...LIW Aviation/Nowcasts....DP Data Acquisition.....DP Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest