Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
388 FXUS62 KKEY 271756 AFDKEY Area Forecast Discussion National Weather Service Key West FL 156 PM EDT Wed Aug 27 2025 ...New AVIATION, PREV MARINE, DISCUSSION, AND FORECAST... .AVIATION... (18Z TAFS) Issued at 155 PM EDT Wed Aug 27 2025 Opted to extend VCSH through 22Z due to continued observed shower activity across the area, most of which is short-lived. Outside of any showers that briefly impact the terminals, VFR conditions will prevail through the TAF period. Surface winds will continue to be generally from the east at near 5 knots, except for higher gusts associated with shower activity. && .PREV DISCUSSION... Issued at 1109 AM EDT Wed Aug 27 2025 A fairly active BYX radar has been detecting widely scattered showers and thunderstorms across the Island Chain and Keys coastal waters through the morning. This activity is being aided by a band of enhanced moisture laid squarely across our area, as depicted by satellite- based precipitable water values of around 1.8 to 2.0 inches. This morning`s 12Z KEY sounding measured 1.90 inches of PWat, which is more moist than 24 hours ago, but dew point depressions notably increase above about 850 mb. This is helping to limit (but not totally prevent) deep convective growth within the current shower activity. That said, between the moisture and the numerous boundaries left behind by the morning activity, it is worth holding onto the 40% PoPs currently in the forecast, and thus no changes are needed for this afternoon. The morning convective activity and associated cloud cover had been keeping surface temperatures a few degrees cooler than they were this time yesterday, but the most recent obs are creeping back up near 90F again, with dew points generally in the upper 70s. A large surface high dominating the eastern CONUS in combination with the Atlantic high to our northeast continue to result in generally light to gentle easterly breezes. && .FORECAST... Issued at 424 AM EDT Wed Aug 27 2025 A stalled frontal boundary is expected to remain in the vicinity of Central Florida for the next few days. This in combination with the ridge over the Atlantic will result in moisture pooling around the Keys and much of the Florida Peninsula for much of the upcoming forecast period. As a result, the forecast now carries basically 40% through the whole time period as it remains too difficult at this time to say which periods will feature the higher or lower rain chances. We do advertise 30% tonight through Thursday night, however, some model guidance does indicate that these PoPs might not be high enough and may be changed in subsequent updates. The catalyst to this pattern will be a stalled frontal boundary to the north along with the ridge over the Atlantic creating a sort of squeeze play across much of the Florida Peninsula and the Keys. None of these weather features are expected to move all that much for a good portion of the next week including through the holiday weekend. There are even some indications that next week might look even wetter once we get past the holiday itself and towards the middle part of the week. Some guidance shows the current stalled frontal boundary shifting slightly further south as the upper trough tries to dig a little bit more and potentially develops a surface low off the coast of the Carolinas. Stay tuned as we continue to fine tune the details heading through the holiday weekend and towards the middle part of next week. && .MARINE... Issued at 1109 AM EDT Wed Aug 27 2025 There are currently no watches, warnings, or advisories in effect across the Florida Keys coastal waters. From synopsis, an early season Canadian high pressure system will continue to traverse the eastern United States over the next few days. As it does, it will act to enhance the pressure gradient slightly across the Florida Keys marine zones. As a result, expect light to gentle breezes this afternoon becoming gentle to moderate during the evening, especially across the Straits of Florida. As the high moves into the Atlantic late week and over the weekend, breezes will shift to the east to southeast and slacken. Increased moisture will support higher shower and thunderstorm coverage by the end of the week and for the weekend. && .PRELIMINARY POINT TEMPS/POPS... Key West 84 91 83 91 / 30 30 30 40 Marathon 82 91 81 91 / 40 30 30 40 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...MC Aviation/Nowcasts....MC Data Acquisition.....MC Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest