Cross Key, Florida Weather Forecast Discussion

246
FXUS62 KKEY 090231
AFDKEY
Area Forecast Discussion
National Weather Service Key West FL
1031 PM EDT Mon Sep 8 2025
...New DISCUSSION, MARINE, AVIATION...
.DISCUSSION...
Issued at 1030 PM EDT Mon Sep 8 2025
It was a busy afternoon and evening across Miami`s coverage area
with multiple advisories and warnings. While not nearly as busy as
our neighbors to the north, KBYX radar detected shower activity
the entire time with the first activity being across the offshore
Gulf waters. Convection on the mainland moved southeastward which
brought a surge of winds to the far Upper Keys, especially Ocean
Reef area. Carysfort Reef Light recorded a wind gust of 29 knots
or 34 mph around 700 pm earlier this evening. This storm that
moved off the mainland did result in a Special Marine Warning
being issued for the eastern Hawk Channel waters and the
northeastern Straits. A few showers formed over the Lower Keys
shortly after sunset resulting in a quick downpour from mainly
Cudjoe Key to Big Pine Key. In the last hour or so, another
outflow boundary moved off the mainland into Florida Bay resulting
in the formation of more showers and thunderstorms. In addition,
scattered showers have developed in the past hour across the
southern Straits mainly south of the Woods Walls with additional
shower activity now forming in the vicinity of Key West.
Temperatures along the Island Chain are in the lower to mid 80s
from the Middle Keys to Lower Keys with upper 70s for the Upper
Keys. Dew points are in the mid to upper 70s. A similar pattern to
recent days remains in place with weak low pressure over the
east-central Gulf and weak high pressure across the Bahamas. This
is resulting in marine platforms around the Keys observing south
to southwest breezes of 5 to 10 knots.
.SHORT TERM FORECAST...
The 00z evening sounding looks similar to recent evenings with a
fairly saturated profile. The PWAT value measured remains quite
high at 2.25 inches which is above the 90th percentile for the
date. The wind profile shows southwesterly winds from the surface
up to around 3000 ft AGL. Overall, we have the moisture, an
outflow boundary moving southwestward through the Keys from off
the south Florida mainland, and other residual boundaries
throughout the Keys waters. Since we have basically all the
ingredients to get shower and thunderstorm activity, no changes
expected to the ongoing forecast.
&&
.MARINE...
Issued at 1030 PM EDT Mon Sep 8 2025
There are currently no watches, warnings, or advisories in effect
across the Florida Keys coastal waters. From synopsis, a surface
trough will remain centered over the eastern Gulf and Florida
Peninsula over the next couple of days. This trough will be slowly
sheared out mid to late week. However, the pressure field in and
around the Keys will generally remain poorly defined. Moisture
will remain above normal. This along with the weak steering
currents will result continued above normal convective potential.
&&
.AVIATION...
(00Z TAFS)
Issued at 1030 PM EDT Mon Sep 8 2025
VFR conditions are expected to persist through the TAF period.
Latest guidance is suggesting that showers and thunderstorms may
develop near the terminals overnight. However, there remains much
uncertainty in the timing and placement of this activity.
Therefore, VCSH was not included in the TAF. We will continue to
monitor and VCSH may be added in subsequent updates. Near surface
winds are expected to remain south to southwest between 3 to 10
knots.
&&
.PRELIMINARY POINT TEMPS/POPS...
Key West  90  79  90  80 /  50  60  60  50
Marathon  89  79  88  80 /  50  50  50  40
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...None.
&&
$$
Public/Marine/Fire...MJV
Aviation/Nowcasts....MJV
Data Acquisition.....DR
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NWS KEY Office Area Forecast Discussion