textproduct: Key West

KEY MESSAGES

- Minor coastal flooding will continue across the Keys around high tide. Moderate coastal flooding will also be possible in the Upper Keys.

- Rain chances will be at or below normal through the early work week, with dewpoints remaining in the lower 70s. - The first strong cold front of the season will likely push through the Keys late next week, with much cooler "sweater weather" possible in its wake.

DISCUSSION

Issued at 1227 PM EST Sun Nov 8 2026 Upper-air isobaric analysis highlights a continued amplified synoptic pattern across the CONUS. A shortwave trough, with a surface reflection of a weak frontal boundary flirting with the Florida Keys, continues to push offshore of New England. Meanwhile, another positively tilted shortwave near Baja California along a southern jet is progressing eastward. The Florida Keys remain dominated by a broad high pressure system extending from the Midwest eastward to the Southeast. This is supporting generally gentle northeasterly breezes, although island heating has also supported occasional shifts to the southeast. Associated confluence has supported a broken island cloud line, mainly in the Lower Keys, but with limited moisture sampled in the 12z sounding at KEY above 850 mb and meager low- and mid-level lapse rates, available local Doppler radars continue to be void of any meteorological echo returns at this early afternoon hour. Due to ample solar insolation and the slightly veered winds relative to the northeasterly direct, temperatures have overachieved today, reaching the mid 80s at most island communities.

The synoptic pattern for the next several days for the Keys will remain relatively unchanged. Any shower activity will be limited to occasional speed surges and localized zones of confluence. Forecast soundings continue to highlight very limited moisture above 850 mb, so any activity should be relatively shallow. A persistence forecast is prudent in this environment, with slight chances for measurable rainfall (10-20%) still seeming appropriate through Wednesday, and highs generally in the mid 80s.

The forecast becomes much more interesting for Thursday through next weekend. A longwave trough will dig across the Eastern Seaboard, reenergized by a shortwave trough progressing in the subtropical jet. Deterministic and ensemble global numerical weather prediction guidance supports this driving the first strong cold front of the season through the Keys late Thursday night or early Friday morning. While confidence continues to increase in this evolution, there remains quite a bit of uncertainty regarding the ultimate strength of this front, tied to the amount of deepening of an associated surface low off the New England coastline. Regardless, the coolest weather of the season thus far for the Keys is nearly certain, with highs struggling to get out of the low to mid 70s for Friday through the weekend, breezy to windy conditions, and low stratus in the wake of the frontal passage.

MARINE

Issued at 1227 PM EST Sun Nov 8 2026 A Coastal Flood Statement remains in effect for the Florida Keys. Boaters can expect less clearance under fixed bridges, especially around the times of high tide. Elsewhere no watches, warnings, or advisories are currently in effect in the Florida Keys waters. From synopsis, a robust high pressure system over the southeastern United States will spread eastward over the next few days. As a result, light to gentle northeasterly breezes will gradually shift further northeasterly and freshen early this week. As the high slides further southeastward into the west-central North Atlantic, breezes will clock around to the east and modestly slacken by mid week. A strong cold front is expected push through the Keys marine zones late Thursday night, with breezes backing to the northwest and freshening in its wake.

AVIATION

(18Z TAFS) Issued at 1227 PM EST Sun Nov 8 2026 Generally dry skies and light winds will continue through this TAF period with VRF conditions prevailing. A broken cloud line is currently struggling to develop along the island chain and should not produce any precipitation or extensive cloud cover. Tonight, a few showers may drift off of the mainland and make their way to the Middle Keys between 03z and 07z.

PRELIMINARY POINT TEMPS/POPS

Key West 84 76 85 76 / 0 10 10 20 Marathon 84 76 85 77 / 0 20 20 20

KEY WATCHES/WARNINGS/ADVISORIES

FL...None. GM...None.