Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
806 FXUS62 KKEY 271533 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1133 AM EDT Fri Sep 27 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 1130 AM EDT Fri Sep 27 2024 The 12z sounding at KEY sampled unidirectional flow extending from the surface to around the 650 mb isobaric level. This layer is quite moist, with sampled relative humidity values throughout this layer registering at or above 70%. Nearby surface observations indicate slackening, modestly confluent flow, as now Tropical Storm Helene continues to trek well away from the Florida Peninsula. KBYX radar is only detecting a few trailing rainbands in the western coastal waters at this late morning hour. For the rest of today, available statistical numerical weather prediction guidance suggests continued wet bouts for the Florida Keys. However, dry, continental air filter filtering in on the back side of Helene coupled with the aforementioned slackening flow seems to suggest much lower rain chances for this afternoon and evening. Have elected to lower measurable rain chances for this first period to levels far below the statistical guidance. The main story for the Florida Keys today will be the residual coastal water flooding, particularly along the bayside waters of the Upper Keys. Despite slackening breezes, tidal levels will likely be slow to recede, and additional coastal flood products will likely be required for several more forecast periods. && .MARINE... Issued at 1130 AM EDT Fri Sep 27 2024 A Coastal Flood Warning remains in effect for the Upper Keys. Residual backup of bayside coastal waters from recently departing Hurricane Helene coupled with fresh south to southwesterly breezes will continue to result in saltwater flooding through this evening. A Small Craft Advisory also remains in effect for all Florida Keys coastal waters. Strong southerly breezes will continue to slacken this afternoon and tonight, as Tropical Storm Helene pushes farther inland across the southern U.S. High pressure building back in to the region will help breezes slacken further and shift easterly over the weekend, and into next week. && .AVIATION... (15Z TAFS) Issued at 1130 AM EDT Fri Sep 27 2024 VFR conditions will prevail at both EYW and MTH island terminals through the TAF period. Shower activity is still possible through this afternoon, but thereafter, dry air will move in to the area prohibiting any further development. Gusty winds of near 25 knots will start to become occasional instead of frequent so will remove the from the TAF later today. Near surface winds will be southerly near 15 knots outside of gusts. && .PRELIMINARY POINT TEMPS/POPS... Key West 89 82 90 82 / 40 50 30 20 Marathon 90 82 91 82 / 40 50 30 20 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...Coastal Flood Warning until 5 AM EDT Saturday for FLZ076. GM...Small Craft Advisory until 5 PM EDT this afternoon for GMZ031>035-042>044-052>055-072>075. && $$ Public/Marine/Fire...BT Aviation/Nowcasts....AP Data Acquisition.....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