Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
368 FXUS62 KKEY 171520 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1120 AM EDT Sun May 17 2026 ...New DISCUSSION, MARINE, AVIATION, PREV DISCUSSION... .KEY MESSAGES... - Very warm and humid conditions will continue across the Florida Keys, raising the risk for heat-related illnesses through the remainder of the weekend and well into next week. - Rain and thunder chances will peak today through Monday, before gradually decreasing. - Breezy conditions are becoming increasingly likely, beginning as early as tonight. && .DISCUSSION... Issued at 1038 AM EDT Sun May 17 2026 Many of us woke up this morning to find some evidence of rainfall, whether it be a few raindrops on the sidewalk or puddles on the roadway. The handful of automated observations we have available reported nearly a tenth of an inch of rainfall in the 12 hour period between 9 PM last night and 9 AM this morning. Radar- derived estimates show similar values, except for a few isolated pockets near Big Pine Key where nearly three quarters of an inch of rain may have fallen. The heaviest showers have remained well offshore of the island chain with our local marine life possibly seeing 1 to 3 inches. The 12Z KKEY sounding from this morning sampled a moderate amount of low and mid level moisture including a calculated PWAT of 1.84". Just looking at the cloud motion on visible satellite imagery, there seems to be some low level convergence in the flow, so pockets of showers and thunderstorms are likely to continue into the afternoon. However, as the environment is worked over, we should see this activity simmer down during the afternoon time. No changes are needed with this morning update. && .DISCUSSION... Issued at 426 AM EDT Sun May 17 2026 Breezy conditions are becoming increasingly likely, beginning as early as tonight. Thereafter, we expect breezy conditions to linger through at least Monday night. Then the high will gradually flatten out as an upper level trough becomes cut-off and sits across the southwestern North Atlantic near the Bahamas. While an easterly flow will persist through the end of the new work week, pockets of relatively drier air will move through, dropping rain chances towards the end of the week. Lastly, a prolonged easterly regime means the air mass will be changing very little if at all. In fact, current guidance suggests that some island communities could tie or set new records for high temperatures during the week. This coupled with dew points in the mid 70s will continue to maintain a limited to elevated risk for heat-related illnesses. && .MARINE... Issued at 1038 AM EDT Sun May 17 2026 There are no watches, warnings, or advisories in effect for the Florida Keys local waters, but Small Craft Should Exercise Caution for increasing winds across the Florida Straits. High pressure centered near Bermuda will lead to generally moderate east to southeast breezes through the rest of the weekend. Showers and thunderstorms will wax and wane across the area. && .AVIATION... (15Z TAFS) Issued at 1038 AM EDT Sun May 17 2026 VFR conditions will prevail at both island terminals through the TAF period, but occasional observations of MVFR CIGs may occur leading up to 20Z due to leftover shower activity across the area. Showers may move over either terminal, but categorical changes arent expected as rain should be light. Prevailing winds at the surface will remain out of the east southeast at 10 to 15 knots. && .PRELIMINARY POINT TEMPS/POPS... Key West 91 81 91 80 / 40 30 30 30 Marathon 87 80 87 80 / 40 30 30 30 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...DP Aviation/Nowcasts....DP Data Acquisition.....DP Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest