FXUS62 KKEY 191544 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1144 AM EDT Sun Apr 19 2026 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... - Seasonable weather conditions are expected to continue through Monday, with mostly to partly sunny skies, near- average temperatures, and light to gentle breezes. - A late-season cold front is expected to arrive Monday night, with potential rain and storms and fresh to strong breezes in its wake. - Small Craft Advisory conditions look increasingly likely across Florida Keys coastal waters Monday night through Wednesday. && .DISCUSSION... Issued at 1100 AM EDT Sun Apr 19 2026 Visible satellite imagery shows a counterclockwise motion among the cloud field across the southern local waters, so we can infer that some cyclonic vorticity is encouraging the shower activity noted on the KBYX radar over the distant Straits this morning. The 12Z KKEY sounding from this morning calculated a PWAT value of 1.22", which sounds like plenty, but this moisture seems to be split between the lower and upper levels of the atmosphere with a deeper layer of dry air in the mid levels. This will inhibit vertical shower growth, so we aren't expecting thunderstorms associated with the current shower activity. The other side of that coin is that we can't rule out occasional, light showers brushing the island chain today. The 0-10k ft mean wind from the morning sounding was only 1.3 knots, or 1.5 mph, impressively light. The balloon likely went through a col region that seems to be somewhere out there, but it is difficult to make out where it is just based on the motion of the clouds. Regardless of the fine details, there is a lot of variability to the low level motion ahead of the approaching cold front well to our north. Our fairly benign forecast is unfolding as expected, so there are no changes needed with this morning update. && .PREV DISCUSSION... Issued at 453 AM EDT Sun Apr 19 2026 A surface high that has seemingly been unmovable will finally shift eastward across the Atlantic and loosen its grip on the Florida Keys. This will leave us in a col region, resulting in light and variable winds developing during the morning and afternoon today. This will be brief as a cold front currently draped across the North Gulf coast will be making slow but steady progress southward over the next 24 to 48 hours. Said cold front will sweep through Monday evening with a blast of northeasterlies. Windy conditions will develop in earnest overnight Monday and continue through Wednesday. A little better moisture will also accompany the front and it will be enough for some scattered showers and possible a few thunderstorms. Given the north to northeast steering flow on Monday, the first areas to see thunderstorms will be the Upper Keys and surrounding coastal waters immediately downwind of the mainland. As the front sweeps through, the remainder of the Keys will see a chance of thunderstorms. Our chance at rain and any accumulations will unfortunately be limited to Monday evening as the front moves through. GFS and ECMWF have both come into agreement that the moisture plume with the front will slide well to our south. There remains a signal on Thursday for another shot at some rain as a potent upper level shortwave pivots southeast across the Gulf and over the Keys. However, this will remain highly dependent on how much moisture we can recover prior to that feature arriving. Otherwise, there are no other discernible features that will make a noticeable dent in our moderate drought conditions within the next 5 - 7 days. && .MARINE... Issued at 1100 AM EDT Sun Apr 19 2026 There are no watches, warnings, or advisories in effect for the Florida Keys local waters. From synopsis, the Florida Keys coastal waters will be situated under a col region this afternoon. This will result in a period of light and variable winds lasting through the early evening. Breezes will freshen slightly Sunday night into Monday morning ahead of an approaching front. This front is poised to sweep through the Keys sometime Monday late afternoon/evening with a strong high pressure quickly filling in the wake on Tuesday. Fresh to strong breezes will develop as early as Monday night, and hazardous marine conditions will continue through at least mid week. && .AVIATION... (15Z TAFS) Issued at 1100 AM EDT Sun Apr 19 2026 VFR conditions will prevail at both island terminals, but occasional observations of MVFR CIGs may occur due to cloud bases near FL020. Any MVFR obs will not last very long, and long term impacts at either terminal are not expected. Light and variable surface winds will assume a northerly direction tonight, but cross wind concerns are low due to winds of 5 to 10 knots. Light showers nearby may lead to occasional VCSH, but TAFs will remain dry. && .PRELIMINARY POINT TEMPS/POPS... Key West 84 74 84 72 / 10 10 10 20 Marathon 83 75 83 72 / 10 10 20 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