Area Forecast Discussion
Issued by NWS Key West, FL

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801
FXUS62 KKEY 160754
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
354 AM EDT Wed Jul 16 2025

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

.DISCUSSION...
Issued at 400 AM EDT Wed Jul 16 2025
Composite overnight satellite-derived vorticity analysis places a
low-level cyclonic system centered around the Big Bend area of the
Florida Peninsula, gradually advecting and propagating westward
along the northern Gulf coastline. Meanwhile, further aloft, a
well-defined Tropical Upper Tropospheric Trough (TUTT) cell
continues its westward trek north of Hispanola, now approaching
the Northern Bahamas. The 00z evening sounding at KEY sampled a
very deep, moist tropospheric profile, along with modestly backed
low- level winds, and limited convective available potential
energy (CAPE) to realize. KBYX Doppler radar trends have been
upwards over the past hour or so, although thunderstorm coverage
has been somewhat limited, likely due to weak boundary collisions
in the light to gentle east to southeasterlies, as well as the
aforementioned limited CAPE to take advantage of. Skies are
generally partly cloudy across the Florida Keys, with temperatures
in the lower 80s (outside of briefly rain-cooled island
communities).

For today, high pressure in the North Atlantic will continue to
build westward. With its axis intersecting somewhere near the
Florida Space Coast, this will aid in freshening east to
southeasterlies. The freshening flow, combined with the continued
deep tropospheric moisture, and the lack of any mid- and upper-
level ridging, will support above normal rain and thunder chances
for today. Current meteorological reasoning suggests coverage
should be greatest through much of the morning hours, then lull
thereafter for much of the afternoon (this is also supported by
most mesoscale short-term guidance as well). Forecast soundings
do suggest an overlapping period sometime in the upcoming evening
and early overnight hours where an accelerated veered wind profile
coincides with great moisture and instability, and we will need
to watch for additional storm development during that period.
Thereafter, the environmental quickly begins to dry out, and near-
climatological rain chances are maintained for the balance of the
work week and over the weekend.

For next week, there is early global numerical weather prediction
ensemble support for yet another decaying frontal boundary to
park off the Southeast, with possible weak cyclogenesis
splintering off the front, diving southwestward towards the
Florida Peninsula. Should this occur, another bout of elevated
rain and thunder chances will be possible by the middle of next
week for the Keys, although plenty of time to monitor the
progress of this potential system. Temperatures will remain
seasonably warm over the next seven days, with highs generally in
the upper 80s, and lows in the lower 80s.

&&

.MARINE...
Issued at 400 AM EDT Wed Jul 16 2025
Scattered showers and thunderstorms are expected in proliferate
in terms of coverage and intensity through at least the late
morning and early afternoon hours. Any stronger storm will be
capable of producing locally gusty winds, as well as suddenly
building and confused seas.

From synopsis, an area of low pressure will continue to slide
westward along the northern Gulf coast. Meanwhile, a strong area
of high pressure will build westward across the North Atlantic
towards the Florida Peninsula, supporting freshening east to
southeast breezes over the next several days. As a second, weak
area of high pressure builds over the eastern Gulf for the second
half of the weekend, easterly breezes will slacken, becoming
light to gentle.

&&

.AVIATION...
(00Z TAFS)
Issued at 400 AM EDT Wed Jul 16 2025
VFR conditions will largely prevail at EYW and MTH through the
TAF period, though expected showers and thunderstorms are likely
to produce periods of sub-VFR conditions at times. Confidence is
high that this will occur, but sufficient confidence in timing is
not enough to pinpoint specific mention in the TAFs for the
moment. VCSH mentions will provide the general timing for now, and
later TAF amendments and routine issuances will cover specifics
as needed. Winds will be gentle from the southeast, becoming
gentle to moderate after sunrise, then slackening and becoming
east to southeast overnight.

&&

.CLIMATE...
On this day in 1888, he daily record low temperature of 68F was
recorded at Key West. This is also the lowest temperature ever
recorded in July at Key West. Temperature records for Key West date
back to 1872.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  91  82  92  83 /  60  40  40  30
Marathon  89  82  90  83 /  60  40  40  30

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...None.
&&

$$

Public/Marine/Fire...BT
Aviation/Nowcasts....MC
Data Acquisition.....MC

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