textproduct: Key West

KEY MESSAGES

-Mainly light to gentle southeast breezes expected through the rest of the day. -Moisture continues to increase resulting in slight chances today. Rain chances further increase going into Monday ahead of the next frontal passage.

-Humid conditions will persist today as dew points potentially reach the upper 70s.

DISCUSSION

Issued at 1111 AM EST Sun Dec 7 2025 Another relatively quiet day is underway across the Florida Keys on this first Sunday of December. After last night's brief sparking of thunderstorms in the outer Straits of Florida off a Cuban land breeze, KBYX radar has been free of any heavy convection with only a few shallow showers detected near the island chain at this time. A few bands of fair weather stratocumulus are drifting over the Keys, but GOES-19 visible imagery notes mostly clear skies otherwise across our CWA. Similar to yesterday, winds have perked up across our waters with Reef observation stations recording light to gentle southeast to south breezes. Warm and humid conditions prevail with temperatures in the lower 80s and dew points in the mid to upper 70s.

This afternoon looks to be a repeat of yesterday. After this morning's brief wind surge, breezes will slacken a few knots but remain light to gentle. Southwesterlies in the low levels of the atmosphere will allow for another possible cloud line set up this afternoon. Cloud line or not, slight rain chances will persist today as this morning's KKEY sounding shows a decent amount of moisture in the levels below 800 mb. CIMSS MIMIC PW also notes a good deal of higher PW values upstream of our southwesterly flow aloft. We must remember that it is indeed not summer anymore, so seeing that our instability levels are similar to that of yesterday, any thunderstorm development (if at all) will likely stay away from island chain and remain in the Straits of Florida.

Tonight, conditions start to change as the stationary front over mainland Florida lumbers south towards our area. This will result in surface breezes freshening and veering to the southwest to west by Monday morning. With this wind shift comes increasing rain and thunder chances that will become more pronounced as a possible prefrontal line of convection associated with another cold front sweeping through the Gulf approaches the Keys tomorrow.

MARINE

Issued at 348 AM EST Sun Dec 7 2025 Light to gentle southeast to south breezes will persist through the morning and early afternoon. Thereafter, a combination of a pre- frontal trough and approaching cold front move in from the north, we will see winds box around the compass while gradually freshening. Cold front passage is expected Monday evening and overnight with a brief period of moderate to fresh northerly breezes. Thereafter, the front will stall across the Florida Keys and Straits of Florida, potentially leading to a more active and unusual weather pattern for this time of year. There is a growing potential for another cold front to pass through towards the end of the week.

AVIATION

(15Z TAFS) Issued at 1111 AM EST Sun Dec 7 2025 VFR conditions are expected to prevail at both EYW and MTH for the rest of today and into tonight. While a few stray showers will be possible near the island chain this afternoon, uncertainty in exact location and isolated coverage will keep mention out of either TAF for now. Near surface winds will be out of the southeast to south at 5 to 10 knots, veering southwest after sunset.

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.