468
FXUS62 KKEY 300237
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
1037 PM EDT Tue Sep 29 2026

...New DISCUSSION, MARINE, AVIATION...

.KEY MESSAGES...

- Moderate to major saltwater flooding of low elevation streets
  and lots is likely to continue over the next few day or so due
  to King Tide. Don`t drive through flooded roadways. Boaters can
  expect less clearance under fixed bridges.

- A Coastal Flood Warning is in effect for the Upper Keys,
  particularly along the sounds, bay side of Key Largo. A Coastal
  Flood Advisory is in effect for the Middle and Lower Keys.

- A wet pattern is expected for the next several days across the
  Keys. This will maintain above normal rain and thunder chances
  through at least Thursday.

&&

.DISCUSSION...
Issued at 928 PM EDT Tue Sep 29 2026

A very wet pattern remains entrenched across our area this
evening. A few features are contributing to this soggy weather. A
very amplified upper level trough stretching down the Atlantic
Coast states and through the Gulf into the Yucatan, has placed
Florida and the eastern Gulf under a broad area of upper level
diffluence. While the best lift, as seen in satellite imagery, appears
to be to our west and northwest, there was more than enough
support across our area. In addition, a spoke of a lower level
Atlantic ridge stretches westward across the Florida Straits. This
is resulting in a veered steering flow that continues to pump deep
tropical moisture northward across the Keys. This evenings
sounding indicated considerable moisture at 2.24 inches of
precipitable water, ample CAPE, and weak low level inhibition. As
a result of all the above, multiple bands of showers and
thunderstorms, some of which were strong, were able to crisscross
the Keys and its waters through the evening. The organized veering
flow was able to generate a few short lived mesocyclones.
Currently, a broad swath of showers and a few thunderstorms
remains aligned across the Lower Keys and the adjacent near
through offshore waters. Convective influences has already
periodically driven temperatures down into the mid 70s at most
island locations, while dew points have slipped to near 70.

The upper level trough will shift southeastward into the eastern
Gulf overnight, while the southern periphery begins balling up
over the Yucatan. This will keep the Keys on its diffluent eastern
periphery. In addition, a southeasterly steering flow around the
Atlantic ridge will continue to stream deep tropical moisture
across our area. Furthermore, the surface ridge axis will
consolidate across the southeastern United States and will likely
result in light to gentle east to southeasterly breezes picking up
to gentle to moderate. As a result of the above, the wet pattern
is not expected to go anywhere through short term. However, due to
the considerable coverage of convection that has repeatedly
flourished across our area through the afternoon and evening, it
is proable that a quieter stretch will eventually set in once the
most recent round of activity finally exhausts itself. At this
time, there is no reason to adjust the currently advertised
likely PoPs. Expect overnight lows to be largely be determined by
rain cooling and will generally range broadly in the 70s. Dew
points may slowly climb towards the mid 70s as the boundary layer
begins to recover.

&&

.MARINE...
Issued at 928 PM EDT Tue Sep 29 2026

A broad surface ridge spanning the eastern United States and the
adjacent Atlantic will maintain gentle to moderate east to
southeasterly breezes across Keys waters overnight. With that
said, winds in the immediate future will be dominated by outflow
boundaries, both new and old, due to the copious convective
activity that worked its way across our waters from just about all
directions. A very wet pattern will remain, however a break will
probably set in over the next few hours due to the atmosphere
having been worked over multiple times.

&&

.AVIATION...
(00Z TAFS)
Issued at 928 PM EDT Tue Sep 29 2026

A wet pattern will remain in place across the Keys through the
overnight period. With that said, the environment is becoming
worked over after an active first half. As a result, there is a
good chance that a sizable break is in store for much of the
overnight period. Aside from convective influences, surface winds
will be light to gentle out of the east to southeast.

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Warning until 7 AM EDT Wednesday for FLZ076.
     Coastal Flood Advisory until 7 AM EDT Wednesday for FLZ077-078.
GM...None.

&&

$$

Public/Marine/Fire...11
Aviation/Nowcasts....11
Data Acquisition.....DR

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