Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
302 FXUS62 KKEY 251855 AFDKEY Area Forecast Discussion National Weather Service Key West FL 255 PM EDT Wed Jun 25 2025 ...New AVIATION... .AVIATION... (18Z TAFS) Issued at 255 PM EDT Wed Jun 25 2025 A lull in convective activity is currently observed across the island chain, however, another line of showers and thunderstorms is approaching MTH. VCSH will likely need to be included in both TAFs once timing solidifies for future storms, which varies depending on the guidance used. Immediate impacts will continue to be handled with short term amendments including TEMPO groups. Near surface winds will be generally out of the east at 10 to 15 knots with some higher gusts before decreasing gradually overnight. && .PREVIOUS DISCUSSION... Issued at 1117 AM EDT Wed Jun 25 2025 Summer is here across the Florida Keys this morning as scattered to numerous showers zip through our area. After a brief lull earlier in the morning, KBYX radar has detected an increase in shower coverage with a field of showers and some embedded thunderstorms erupting over the Straits of Florida, Florida Bay, and the island chain. Any one shower is generally shallow, fast moving, and therefore not dropping too much rain over land, but a couple overachievers have generated rain rates over a half an inch per hour along with wind gusts up to 30 knots, and occasional to frequent lightning strikes. Meanwhile, moderate to fresh easterly breezes along the Reef have diminished from earlier this morning and are now comfortably in the moderate category outside of convective gusts. Increased cloud cover associated with ongoing precipitation is keeping temperatures across the island chain in the lower 80s regardless of if rain has fallen. CIMSS mean steering layer (250-850 mb) streamlines note that the mid to upper level trough is centered just west of The Bahamas. Indeed, it is also present as cyclonic motion observed in GOES-19 visible imagery on the tops of storms erupting across the southeast Florida coast and central north coast of Cuba. While mesoscale forcing from boundaries still looks to be the dominating force in the forecast, this extra ventilation from this troughing may help some stronger storms amid shallow showers, especially as more moist air advects in from the east. Above normal rain chances for this time of year are certainly appropriate and may need to be slid higher if this trend continues. && .FORECAST... Issued at 400 AM EDT Wed Jun 25 2025 Minimal changes were made to the previous full forecast iteration conducted last night, with overall meteorological reasoning remaining largely unchanged. CIMSS satellite-derived vorticity products highlight a well- defined upper-level low east of the Florida Space Coast, with a second low-level cyclonic feature in the vicinity of the Greater Antilles. These features will continue to break the ridging that typically bridges the Keys this time of year for at least the next 36 hours or so. This will act to slacken gradient breezes, supporting possible island cloud line formation late this morning or early afternoon. Although the upper-level low should remain displaced northeastward of the Keys, it should provide a good source for ventilation aloft, and thus would not be surprised to see a few stronger storms emerge. Interactions of associated residual outflow boundaries will be the primary source for triggering additional storms through Thursday night (mesoscale storm processes). Thereafter, global aerosol forecast products are insistent on a wave of Saharan dust reaching the mid-levels of the atmosphere by sometime Friday. As is always the case, we will have to monitor whether the leading edge of this dust can provide a source for ascent (similar to dry-line dynamics) and brief additional storminess. Thereafter, mainly dry conditions will likely rule the Keys through the weekend. The climatological ridge should reestablish itself in this period through early next week, with an extended period of gentle to moderate east to southeast breezes expected. Outside of any brief rain-cooled periods, conditions will remain seasonably warm and muggy for the Keys for the next seven days. && .MARINE... Issued at 255 PM EDT Wed Jun 25 2025 No watches, warnings, or advisories are currently in effect for the coastal waters of the Florida Keys. From synopsis, a retrograding upper-level low currently centered east of the Florida Space Coast will support weakened ridging over the next couple of days. Gentle to moderate easterly breezes today will veer to the east to southeast and slacken tonight through Friday night. Ridging will once again strengthen over the weekend, supporting modestly freshening east to southeast breezes. && .CLIMATE... On this day in 1992, the daily record rainfall of 5.14" was recorded at Key West. This is also the wettest day ever recorded in June in Key West. Rainfall records for Key West date back to 1871. && .PRELIMINARY POINT TEMPS/POPS... Key West 80 88 81 89 / 40 40 40 30 Marathon 80 88 81 89 / 40 40 40 30 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...JAM Aviation/Nowcasts....JAM Data Acquisition.....JAM Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest