textproduct: Key West

KEY MESSAGES

- Coastal flooding will continue through the next several days, especially in the Upper Keys.

- A wet, stormy period will continue through this evening. Locally heavy rainfall, especially when coincident with high tides, will exacerbate coastal flooding impacts.

- Much drier conditions are expected for Tuesday through the remainder of the work week.

SHORT TERM

(Overnight) Issued at 930 PM EST Mon Nov 2 2026

Showers and thunderstorms gradually focused further up the island chain early this evening with isolated activity continuing where backing lower tropospheric winds remain confluent. Otherwise convection flared up over the western Straits on the southeast periphery of a persistent mid-level low, likely tapping a slightly drier middle layer north of western Cuba with short-duration, vigorous outflow boundaries propagating northeast/eastward. This shallow disruption with 1,000-foot depth of northwesterly wind was noted at sounding time at KEY. Deeper moisture remained to the east, although the values at KEY remained impressive with the precipitable water still between the 75th and 90th percenties for thedate. The mid/upper troughing continues to our west, dropping various small vorticity maxima southward toward the Yucatan Channel.

While the outflow may have worked the atmosphere into a more stable state, narrow CAPE remains above the surface with an expected increase in convective coverage in the early morning hours. And easterly wind surge will impact the upper Keys coastal waters, rippling westward at lesser magnitude overnight. No significant changes were necessary for the forecasts this evening, although the chance to likely PoPs are more apt to be realized closer to sunrise.

PREV DISCUSSION

Issued at 145 PM EST Mon Nov 2 2026

This active wet pattern is thanks to an mid/upper level trough that has become cut-off temporarily and is situated just to our southwest and west. In the lower levels, we are situated on the western periphery of an Atlantic Ridge with an area of cyclonic flow under the aforementioned cut-off. The easterly flow in the low levels from the ridge is providing ample moisture. This is helping to fuel storms that have developed within this broad area of convergence.

The upper level cut-off low will weaken over the next 24 to 36 hours and pushed eastward as the next upper level trough approaches from the west. Though the upper level feature will be weakening, we will continue to see above normal rain chances lingering into Wednesday, before returning closer to normal towards the end of the week. By the weekend, the upper level pattern becomes more zonal for the Gulf Basin and Florida Peninsula, ushering in dry conditions. We're keeping an eye on a potential dry frontal passage early next week which could lead to freshening breezes. Stay tuned!

MARINE

Issued at 930 PM EST Mon Nov 2 2026 Easterly winds are freshening this evening mainly over the eastern Straits and Hawk Channel, and are expected to gradually decrease to gentle to moderate speeds Tuesday morning. High pressure offshore the Mid Atlantic States will maintain gentle to occasionally moderate east winds through late Tuesday. Elevated northerly swell will persist through Tuesday for the waters southeast of the Upper Keys. Broad wind convergence across the marine zones will keep shower and thunderstorm chances above normal through Wednesday. Expect slackening breezes and drier air gradually decreasing rain and thunder chances during the latter portion of the week.

AVIATION

(00Z TAFS) Issued at 930 PM EST Mon Nov 2 2026 Convection has become isolated, mainly impacting waters east of MTH this evening. A gradual increase in shower and thunderstorm coverage is expected overnight with VCSH set by 03/08Z. There will likely be minimums in convective coverage during the day Tuesday, but very difficult to time. Otherwise northeast to east winds will becoming more easterly, picking up a few knots to 6 to 10 knots during the early morning hours, with little variation throughout Tuesday.

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Advisory until 5 AM EST Tuesday for FLZ076.

GM...None.