581
FXUS62 KKEY 151910
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
310 PM EDT Sat Jun 15 2024

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

.DISCUSSION...
Issued at 310 PM EDT Sat Jun 15 2024
KBYX radar has remained active for much of the day with mostly
stratiform rain for the western waters, Island Chain and the
nearshore waters to the north. To the south of the Chain, the
activity becomes more convective with scattered thunderstorms
especially across the distant Straits of Florida. GOES 16 Visible
satellite imagery continues to show a band of clouds oriented
east to west across the western Atlantic through Florida and into
the Gulf of Mexico rather than northeast to southwest like
earlier this morning. This has kept temperatures in check today
with Island Chain communities observing near 80 degrees with a few
locations in the lower 80s. Dew points are in the lower to mid
70s. The aforementioned boundary in this morning`s discussion
seems to have slowly encroached a little bit further north with
marine platforms south of the Keys observing east to southeast
winds of 5 to 10 knots with Sand Key observing 15 to 20 knots.
Marine platforms north of the Keys are observing northeast to east
winds of 5 to 10 knots. Island Chain communities are observing
near 10 mph along the Middle to Upper Keys with 10 to 15 mph for
the Lower Keys.

.FORECAST...
The end of the wet pattern is upon us as a ridge over the
Caribbean and Hispaniola to western Cuba continues to slowly nudge
its way northwestward through tonight. This will be happening as
another fairly strong surface high moving across the eastern
United States moves out in the Atlantic off the New England coast
but building southward as it does so. The two of these working in
tandem with each other will help to choke off the tropical
moisture plume that has plagued Florida for the last several days
shifting this plume westward into the Gulf and then eventually
making the North Gulf Coast from Louisiana to Texas very wet in
the days to come. There may also be the potential for something
tropical in nature to develop, though, weak if has enough time to
develop over the Southwestern Gulf of Mexico and then move into
either Texas or Eastern Mexico coastline. The National Hurricane
Center (NHC) has an area highlighted across the southwestern Gulf
for 50% chance for development over the next 7 days.

The aforementioned surface high moving across the eastern United
States and then off the New England Coast will build southward
strengthening the pressure gradient across much of Florida due to
lower pressure in the Caribbean due to the Central American Gyre
developing. This will result in a prolonged period of potentially
near breezy to breezy conditions for the Chain over the course of
this next week.

Regarding moisture, since much of this will be shifting northwest
and away from the Keys, we will return to your regularly scheduled
programming in terms of PoP chances for this time of the year
which is ~25%. Therefore, Sunday and Sunday night remain at 20%
with Monday through Tuesday night remaining at 30% due to a slight
uptick in moisture early next week.

Then things get interesting, the latest guidance is showing the
risk for the vorticity in the upper levels that was originally
associated with recent rains across Florida coming back to the
west. However, model guidance shows this festering for a little
bit over the western North Atlantic to the north of Hispaniola and
Puerto Rico. This vort maxima will be waiting on the upper level
ridge that will bring the prolonged heat to the Midwest and
Northeast to pick this energy up and shift it back to the west.
As we know, we have clockwise flow around a high so once this gets
picked up it will most likely have only one place to go. What
becomes of this is too early to tell but the risk is there for
tropical moisture to potentially make a reappearance for at least
some part of Florida mid to late next week resulting in PoPs being
increased to 40% in this time frame. One thing to also mention is
the flow looks to be fast so anything that might try to develop
wouldn`t have much time to do so.

&&

.MARINE...
Issued at 310 PM EDT Sat Jun 15 2024
Small Craft Should Exercise Caution (SCEC) for Increasing winds
are headlined across the Florida Keys coastal waters tonight,
except for eastern Hawk Channel and the eastern Straits. The next
week looks to bring a prolonged period of breezy conditions to the
Keys with the potential for Small Craft Advisories especially
across the westernmost waters. Therefore, Small Craft Advisory may
be required Sunday was headlined for the offshore Gulf waters,
western Hawk Channel, and the western Straits. From synopsis, gentle
to moderate breezes this evening will gradually increase over the
next couple of days due to high pressure building in from the
north and falling pressures near the Yucatan Peninsula and Bay of
Campeche. Moderate to fresh breezes will continue through mid week
with winds tending stronger especially across our southwestern
and western waters.

&&

.AVIATION...
(18Z TAFS)
Issued at 310 PM EDT Sat Jun 15 2024
Showers and thunderstorms have developed upstream in the Straits
of Florida and are moving towards the island chain. While rain has
remained mostly light over the past few hours, heavier showers
will likely move over the terminals in the next few hours. TEMPOs
will issued as necessary, as these thunderstorms will bring sub-
VFR, gusty winds, and possible lightning strikes near or over the
terminals. Outside of convection, winds will generally be from the
northeast to east at 5 to 10 knots, becoming east to southeast
and increasing to 10 to 15 knots tomorrow morning.

&&

.CLIMATE...
On this day in 1887, the daily record rainfall of 3.57" was
recorded in Key West. Rainfall records for Key West date back to
1871.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  81  88  82  89 /  40  30  20  20
Marathon  81  88  82  90 /  30  20  20  20

&&

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

$$

Public/Marine/Fire...MJV
Aviation/Nowcasts....NB
Data Acquisition.....DR

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