Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
307 FXUS62 KKEY 080330 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1030 PM EST Sun Dec 7 2025 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... -Mainly light to gentle south to southwest breezes expected through the overnight becoming southwest to west around daybreak. -Breezes continue to clock around the compass becoming west to northwest by late Monday as well as freshen to gentle to moderate breezes as the cold front approaches. -In the wake of frontal passage sometime late Monday/Monday evening, breezes further clock to the north to northeast by early Tuesday. -Peak rain chances are expected overnight and Monday as a frontal boundary approaches the Keys. Any shower will be capable of becoming a thunderstorm. && .DISCUSSION... Issued at 1029 PM EST Sun Dec 7 2025 The Keys continue to remain on the very warm and tropical side of things this evening. Temperatures along the Island Chain are in the upper 70s with some locations still at 80 degrees at this hour. The cool spot is the Big Pine Key RAWS which continues the theme of radiational cooling for the 3rd night in a row observing 73 degrees this past hour. Dew points are tropical in the mid to upper 70s. However, this pattern is about to change! A stationary front is currently draped across the central Florida Peninsula and slowly drifting south-southeastward. This front was responsible for some strong storms this evening around the Space Coast west to the Tampa area. KBYX radar has mostly remained quiet across the Keys this evening. In the last hour or so, some showers have been detected across the southwestern distant Straits of Florida moving northeastward. The Keys remain in overall weak synoptic flow for time being as the col region remains. However, winds have been clocking around the compass since last evening. Marine platforms are observing south to southwest breezes between 5 to 10 knots as the front starts its approach. .SHORT TERM FORECAST... The 00z evening sounding continues to moisten up this evening as well as becoming unstable. The wind profile has also been becoming more representative of supporting shower activity. Winds at 1000 ft AGL are due south near 10 knots with winds veering to southwesterly at 3000 ft AGL and increasing to near 15 knots. The PWAT value measured was 1.6 inches which is above the 75th percentile for the date. Instability also continues to increase with a CAPE value being measured at almost 2000 J/kg. Based on the above, all the ingredients are coming together for an active next few periods. We have the trigger being the frontal system approaching, instability, and moisture. Therefore, no changes to the forecast were done this update. One of the reasons for this is even though most ingredients are coming together, the sounding does show some dry air in a few layers which may inhibit more widespread shower and storm coverage. Also, with the south to southwest winds, there is the possibility that temperatures might not drop out of the upper 70s in some locations. && .MARINE... Issued at 1029 PM EST Sun Dec 7 2025 There are currently no watches, warnings, or advisories in effect across the Florida Keys coastal waters. From synopsis, mainly light to gentle south to southwest breezes will continue to veer to the southwest to west overnight as a stationary front over mainland Florida sinks south. Meanwhile, a weather system moves out of the ArkLaTex region and into the Southeast U.S. The attendent cold front will sweep through Monday night with a brief period of moderate to fresh breezes. The potential exists for a more active weather pattern as the front stalls out across the Straits of Florida for most of the week. && .AVIATION... (00Z TAFS) Issued at 1029 PM EST Sun Dec 7 2025 VFR conditions are expected to persist through much of the overnight period. A stationary front currently draped across central Florida extends southwestward into the Gulf. This front will begin to move southward as a cold front overnight through Monday. Moisture will increase as a result leading to an increase in coverage of showers and potentially isolated thunderstorms, especially after 08/06z. The better chance time for showers impacting the terminals looks to be around and after 08/12z. Therefore, VCSH was placed into the TAF for this time. However, a shower before that cannot be ruled out. Any shower/storm will be capable of briefly reducing CIGs and VIS to MVFR conditions, brief heavy rain, an occasional lightning strike, and gusty winds. && .PRELIMINARY POINT TEMPS/POPS... Key West 84 74 82 70 / 20 40 50 40 Marathon 82 75 82 70 / 20 40 40 30 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...MJV Aviation/Nowcasts....MJV Data Acquisition.....DR Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest