Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
932 FXUS62 KKEY 201520 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1120 AM EDT Thu Jun 20 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 1105 AM EDT Thu Jun 20 2024 Composite satellite imagery highlights broad cyclonic (counterclockwise) flow engulfing the Florida Peninsula, including the Florida Keys. At the surface, expansive high pressure centered to the north of Bermuda is bridging two areas of low pressure: one associated with Tropical Storm Alberto centered over eastern Mexico, and another weak area of low pressure just to the east of the Northern Bahamas. The relative locations of these features has resulted in a slowly waning surface pressure gradient, consistent with modestly slackened easterly breezes this morning. The 12z sounding at KEY sampled quasi-steady geopotential heights at virtually all sampled geopotential heights. The sounding also revealed modest dry air intrusion in the 925-850 isobaric layer. However, forced ascent from the aforementioned cyclonic features has been able to overcome this dry air (at least south of the island chain). For the rest of today, scattered, mainly light passing showers and isolated thunderstorms will certainly be possible. Undulations of dry and more moist air will likely continue over the next 24 hours, as the surface low continues to progress to the west northwest towards northern Florida. Middle of the road PoPs (around 50%) seems appropriate based on this scenario. Outside of canceling the Small Craft Advisory for decreasing winds and subsiding seas, no additional changes proposed to inherited forecast. && .MARINE... Issued at 1105 AM EDT Thu Jun 20 2024 Small Craft Should Exercise Caution headlines are posted for all Florida Keys coastal waters. From synopsis, 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 through this evening. A second, weak area of low pressure currently east of the Bahamas 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... (15Z TAFS) Issued at 1105 AM EDT Thu Jun 20 2024 VFR conditions will prevail at both EYW and MTH through the TAF period. Shower activity will return later this afternoon into the evening so VCSH is included from 20z onward. Near surface winds are easterly at near 15 knots with gusts at times of up to 25 knots. && .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 / 50 40 40 50 Marathon 88 81 89 82 / 50 30 40 50 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...BT Aviation/Nowcasts....AP Data Acquisition.....BT/AP Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest