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 854 PM EST Sun Nov 8 2026 KBYX radar has detected a few showers in the distant Straits and Florida Bay waters over the last few hours. These showers have produced moderate to heavy downpours while remaining mostly stationary. Nighttime Microphysics reveals that outside of the areas of light showers, not much cloud coverage is elsewhere. Temperatures across the island chain are near 80F with dew points in the mid 70s making for a somewhat muggy night out. Along the Reef, marine locations are recording mostly east winds of 5 to 10 knots. Tonight's 00z sounding did contain more moisture in the lower levels than we have been seeing in previous days, explaining the slight uptick in shower coverage experienced tonight. Overnight into tomorrow morning slight chances of showers will continue to pop up but due to dry air, further development will be limited. Northeast to easterly winds will slightly veer to become more easterly and freshen from 5 to 10 knots tomorrow afternoon. A Coastal Flood Statement remains in effect for all of the Florida Keys with minor flooding possible.

PREVIOUS 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 854 PM EST Sun Nov 8 2026 A Coastal Flood Statement is in effect for the Florida Keys. Elsewhere, no watches, warnings, or advisories are currently in effect. 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 shift to the northeast to east and modestly 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 or Friday morning, with breezes backing to the northwest and freshening in its wake.

AVIATION

(00Z TAFS) Issued at 854 PM EST Sun Nov 8 2026 VFR conditions will prevail at both EYW and MTH through the TAF period. Dry air will limit any shower development therefore no mention of VCSH. Near surface winds will be northeast to east at 5 to 10 knots through tomorrow morning.

KEY WATCHES/WARNINGS/ADVISORIES

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