Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
581 FXUS62 KKEY 151910 AFDKEY Area Forecast Discussion National Weather Service Key West FL 310 PM EDT Sat Jun 15 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 310 PM EDT Sat Jun 15 2024 KBYX radar has remained active for much of the day with mostly stratiform rain for the western waters, Island Chain and the nearshore waters to the north. To the south of the Chain, the activity becomes more convective with scattered thunderstorms especially across the distant Straits of Florida. GOES 16 Visible satellite imagery continues to show a band of clouds oriented east to west across the western Atlantic through Florida and into the Gulf of Mexico rather than northeast to southwest like earlier this morning. This has kept temperatures in check today with Island Chain communities observing near 80 degrees with a few locations in the lower 80s. Dew points are in the lower to mid 70s. The aforementioned boundary in this morning`s discussion seems to have slowly encroached a little bit further north with marine platforms south of the Keys observing east to southeast winds of 5 to 10 knots with Sand Key observing 15 to 20 knots. Marine platforms north of the Keys are observing northeast to east winds of 5 to 10 knots. Island Chain communities are observing near 10 mph along the Middle to Upper Keys with 10 to 15 mph for the Lower Keys. .FORECAST... The end of the wet pattern is upon us as a ridge over the Caribbean and Hispaniola to western Cuba continues to slowly nudge its way northwestward through tonight. This will be happening as another fairly strong surface high moving across the eastern United States moves out in the Atlantic off the New England coast but building southward as it does so. The two of these working in tandem with each other will help to choke off the tropical moisture plume that has plagued Florida for the last several days shifting this plume westward into the Gulf and then eventually making the North Gulf Coast from Louisiana to Texas very wet in the days to come. There may also be the potential for something tropical in nature to develop, though, weak if has enough time to develop over the Southwestern Gulf of Mexico and then move into either Texas or Eastern Mexico coastline. The National Hurricane Center (NHC) has an area highlighted across the southwestern Gulf for 50% chance for development over the next 7 days. The aforementioned surface high moving across the eastern United States and then off the New England Coast will build southward strengthening the pressure gradient across much of Florida due to lower pressure in the Caribbean due to the Central American Gyre developing. This will result in a prolonged period of potentially near breezy to breezy conditions for the Chain over the course of this next week. Regarding moisture, since much of this will be shifting northwest and away from the Keys, we will return to your regularly scheduled programming in terms of PoP chances for this time of the year which is ~25%. Therefore, Sunday and Sunday night remain at 20% with Monday through Tuesday night remaining at 30% due to a slight uptick in moisture early next week. Then things get interesting, the latest guidance is showing the risk for the vorticity in the upper levels that was originally associated with recent rains across Florida coming back to the west. However, model guidance shows this festering for a little bit over the western North Atlantic to the north of Hispaniola and Puerto Rico. This vort maxima will be waiting on the upper level ridge that will bring the prolonged heat to the Midwest and Northeast to pick this energy up and shift it back to the west. As we know, we have clockwise flow around a high so once this gets picked up it will most likely have only one place to go. What becomes of this is too early to tell but the risk is there for tropical moisture to potentially make a reappearance for at least some part of Florida mid to late next week resulting in PoPs being increased to 40% in this time frame. One thing to also mention is the flow looks to be fast so anything that might try to develop wouldn`t have much time to do so. && .MARINE... Issued at 310 PM EDT Sat Jun 15 2024 Small Craft Should Exercise Caution (SCEC) for Increasing winds are headlined across the Florida Keys coastal waters tonight, except for eastern Hawk Channel and the eastern Straits. The next week looks to bring a prolonged period of breezy conditions to the Keys with the potential for Small Craft Advisories especially across the westernmost waters. Therefore, Small Craft Advisory may be required Sunday was headlined for the offshore Gulf waters, western Hawk Channel, and the western Straits. From synopsis, gentle to moderate breezes this evening will gradually increase over the next couple of days due to high pressure building in from the north and falling pressures near the Yucatan Peninsula and Bay of Campeche. Moderate to fresh breezes will continue through mid week with winds tending stronger especially across our southwestern and western waters. && .AVIATION... (18Z TAFS) Issued at 310 PM EDT Sat Jun 15 2024 Showers and thunderstorms have developed upstream in the Straits of Florida and are moving towards the island chain. While rain has remained mostly light over the past few hours, heavier showers will likely move over the terminals in the next few hours. TEMPOs will issued as necessary, as these thunderstorms will bring sub- VFR, gusty winds, and possible lightning strikes near or over the terminals. Outside of convection, winds will generally be from the northeast to east at 5 to 10 knots, becoming east to southeast and increasing to 10 to 15 knots tomorrow morning. && .CLIMATE... On this day in 1887, the daily record rainfall of 3.57" was recorded in Key West. Rainfall records for Key West date back to 1871. && .PRELIMINARY POINT TEMPS/POPS... Key West 81 88 82 89 / 40 30 20 20 Marathon 81 88 82 90 / 30 20 20 20 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...MJV Aviation/Nowcasts....NB Data Acquisition.....DR Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest