Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
081 FXUS62 KKEY 081932 AFDKEY Area Forecast Discussion National Weather Service Key West FL 332 PM EDT Sat Jun 8 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 216 PM EDT Sat Jun 8 2024 It has been a fairly typical June day across the Florida Keys, albeit the light southerly steering is a little odd. Isolated to widely scattered showers developed along a tongue of warm air advection spreading north through the Straits late this morning. There have been very few thunderstorms near the island chain. Coverage is on the wane and could be related to Cuban shadow spreading north, or to the collapsing flow. Regional satellite imagery highlights a large expanse of deep convection over the Bahamas and the Western Caribbean. The Western Caribbean clusters are persistent and increasing in coverage within the confluent and convergent easterlies. Through the breaks in the clouds, visibile imagery suggests a little bit of dust may be joining the fray. Surprisingly, the Yucatan is suppressed. The axis from southern Belize through the Bahamas is a favored zone for ascent. .FORECAST... The main story through the short term will be the weak southerly steering featuring meager nightly surges, followed by diminished flow during the afternoon. On-the-whole, the vertical profile will support moist convection, although weak large scale subsidence will limit the overall coverage. We held at 40% through Sunday night. Our confidence is increasing for an extended period of unsettled weather featuring fresh breezes, periods of thundery squalls, and locally heavy rainfall. This pattern change will be due to a developing Central American Gyre (CAG) and the periodic spokes of tropical moisture spreading north along its northeastern flank. There remains a large dichotomy between the global solutions, although the drier Euro solutions have trended wetter in the past 24-hours. The heavy weather may begin as early as Monday, and could last into next weekend. We continue to highlight 60% rain/thunder chances Tuesday through Thursday, but this may be too short of a window for likely rain chances. We trended the wind magnitudes upwards into the 15 to 20 knot range, once again, this may be underdone. Multiday rainfall totals from the ensemble means suggest values between 5 and 10" are in play. Rainy season may turn on with a vengeance. && .MARINE... Issued at 216 PM EDT Sat Jun 8 2024 The pattern will feature weak high pressure over the western North Atlantic and a frontal boundary stalled over northern Florida. This will result in light to gentle southerly breezes across the Keys coastal waters tonight through Monday. Freshening breezes and an extended period of unsettled weather may begin as early as Tuesday and will persist through Thursday night. && .AVIATION... (18Z TAFS) Issued at 216 PM EDT Sat Jun 8 2024 VFR conditions are mostly expected at the terminals through the TAF period. KBYX radar shows mainly a few showers in the vicinity of the MTH terminal with the area around KEYW remaining quiet for now. Guidance does continue to show the threat for showers or even an isolated thunderstorm between now and at least 09/00z this evening. There may still be a stray shower or storm after this time but confidence is low and therefore decided to drop VCSH from the TAF after that time. Any shower or storm through this evening will be capable of producing brief gusty winds in and near convection as well as MVFR conditions for CIGs and VIS. Near-surface winds outside of convection will be generally south to southwesterly at 5 to 10 knots. && .CLIMATE... On this day in Keys weather history, the daily record warm low temperature of 86 degrees was recorded in Marathon set back in 2019. This also ties for the warmest low temperature ever recorded in June and the all-time warmest low for the Marathon area. Temperature records for Marathon date back to 1950. OF NOTE In 1966, Hurricane Alma moved north off of Cuba and intensified to a Category 3 hurricane and passed about 35 miles west of Key West. The Dry Tortugas measured sustained winds of 125 mph while Key West measured winds of 60 mph with gusts to 70 mph. Hurricane Alma was the only hurricane to affect the Keys during the month of June in the last hundred years. && .PRELIMINARY POINT TEMPS/POPS... Key West 81 90 81 90 / 40 40 40 50 Marathon 82 90 82 91 / 40 40 40 50 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...CLR Aviation/Nowcasts....MJV Data Acquisition.....MJV Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest