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000
FXUS62 KKEY 251822
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
222 PM EDT WED MAY 25 2016

.DISCUSSION...
Active radar day with scattered showers and thunderstorms flirting
with the Keys island chain from the middle to lower Keys, and moreso
over the Straits of Florida. Winds have freshened from the east, with
gusts reported at or above 20 knots at the taller CMANS south of the
island chain. Away from the rain-cooled and cloudy lower Keys,
temperatures are between 85 and 90 degrees.

High surface pressure will strengthen a little more towards its
expected peak intensity in the western Atlantic, off the southeast
coast of the United States tonight. Local winds should remain fresh
for much of tonight. But the Straits of Florida should feel the
highest sustained winds with accompanying gusts before beginning to
wane during the day Thursday. MIMIC imagery of moisture shows the
Keys are right on the northern cusp of higher moisture. Drier air is
more evident over the mainland as shallow cumulus has been the best
to developed there thus far into the afternoon. A trough through the
middle and upper levels will continue to reside just to the east of
the Florida peninsula over the next couple of days. Closer to the
surface, lower pressure is expected to form along a decaying trough
stretching far east from the Bahamas. Similar to the last few
forecast cycles, the large scale GFS and ECMWF are pulling a defined low
closer to the southeast coast of the United States by this weekend.
The GFS is not as robust on its latest solution when compared to its
previous few runs. And it does keep a more elongated trough along
the southeast coast, which should lead to a higher probability of
unsettled weather there. Closer to the Keys, numerical MOS numbers
are very close to what we have been advertising through the bulk of
the coming forecast, as far as rain chances are concerned. And, based
on the expected dynamics and available moisture, feel no need to
deviate far from them. However, did decide to include thunder for
each period beyond Thursday. One could argue for less available
convective energy, but a slight chance for thunder shouldn`t be ruled
out for any period through the end of the forecast. In general, a
small change. As far as temperatures, there should not be any large
day-to- day variations for any location away from isolated showers.
They should be at or slightly above seasonal average into the middle
of next week.

&&

.MARINE...
As stated above, the Straits of Florida should feel the highest
sustained winds overnight with some gustiness. Seas are also expected
to build above the Small Craft Advisory criteria of 7 feet there.
This should not be a long-term episode, but enough to justify the
headline. Northeast to east winds will remain fresh elsewhere, with
an Exercise Caution headline for small craft. Beyond Thursday, expect
moderate or even gentle breezes across all coastal waters surrounding
the Florida Keys.

.AVIATION...VFR will prevail at the EYW and MTH terminals this
evening and overnight. Scattered thunderstorms will reach the
vicinity of EYW between 18-20Z. Average storm motion will be from
the east-northeast at 15 KTS. Prepare for temporary convective wind
gusts near 25 knots and IFR CIG/VIS. Precipitation chances will
decrease overnight as gusty easterly winds resume across the island
chain.

&&

.CLIMATE...May 25th, on this date in Key West climate history, in
1995, the daily record warm low temperature of 82F was recorded.
This is also tied for the warmest low temperature ever recorded in
the month of May. Temperature records in Key West date back to 1872.

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...Small Craft Advisory until 8 AM EDT Thursday for GMZ052>055-
     072>075.

&&

$$

PUBLIC/MARINE.........04
AVIATION/NOWCASTS.....CLR
DATA COLLECTION.......Fling

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000
FXUS62 KKEY 251409
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
1009 AM EDT WED MAY 25 2016

.DISCUSSION...
Scattered showers and thunderstorms have been moving westward between
10 and 15 knots in the waters surrounding the Florida Keys this
morning, and across portions of the Keys island chain. More
recently, the stronger cells have been in the Straits while lingering
lighter showers have been close to the island chain. Winds have been
steadily increasing across the service area, with speeds currently
averaging slightly above 15 knots at the available CMAN sensors.
Temperatures are climbing through the middle 80s.

The early morning local sounding sampled an airmass on the back side
of decaying showers and thunderstorms. Some of the winds aloft may
have suffered on that account...namely a deeper than warranted
easterly breeze. Regardless, we are moist and unstable and expect the
the lower winds to back slightly. This orientation should be
favorable for a cloud line through the afternoon, and with colliding
small scale boundaries nearby, a 30 percent probability of measurable
precipitation still looks good for the island chain. A zone update is
planned shortly just to remove some transitional wind wording from
the early morning issuance. All other sensible weather elements are
advertised well.

&&

.MARINE...
As with the zones, the only change expected on the upcoming marine
update will be to set winds more to the northeast/east initially.
Most of the marine zone groupings will have exercise caution
headlines due to wind speeds of 15 to 20 knots. If you have boating
plans for tonight, especially in the Straits, plan for the
probability of a small craft advisory as winds peak overnight, and
seas may build enough to surpass the criteria. More moderate breezes
and seas conditions are expected later in the work week and through
the holiday weekend.

&&

.AVIATION...
VFR will prevail at the EYW and MTH terminals this afternoon.
However...scattered thunderstorms will reach the vicinity of both
terminals. Average storm motion will be from the east at 10 to 15
KTS. The best chances for impacts to flight operations will be late
this morning then again early this evening. Prepare for convective
wind gusts near 25 knots and IFR CIG/VIS. Precipitation chances will
decrease overnight as gusty easterly winds resume across the island
chain.

&&

.CLIMATE...May 25th, on this date in Key West climate history, in
1995, the daily record warm low temperature of 82F was recorded.
This is also tied for the warmest low temperature ever recorded in
the month of May. Temperature records in Key West date back to 1872.

&&

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

&&

$$

PUBLIC/MARINE.........04
AVIATION/NOWCASTS.....CLR
DATA COLLECTION.......Chesser

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000
FXUS62 KKEY 241809
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
209 PM EDT TUE MAY 24 2016

.DISCUSSION...
Isolated showers accompanied by a few thunderstorms have meandered in
the atlantic waters offshore from the upper Keys, just to the
south/southeast of Molasses Reef Light. Additional showers and
thunderstorms just to the north of Florida Bay have moved very little
as well. Winds have acquired an easterly component all
locations...turning slightly to the southeast in the Straits.
Temperatures are between 85 and 90 along the island chain.

High surface pressure currently centered along the South
Carolina/Georgia Coast will continue to settle southeastward into
the western north Atlantic. This will continue to freshen the local
winds from the east/northeast over the next few periods. However, the
latest cycle of the large scale models suggest that the winds may not
accelerate as much locally. Regardless, the forecast reasoning has
not changed much from our previous few cycles for the Florida Keys.
Expect at least a few showers and thunderstorms over the next few
days as mid to upper level narrow trough sharpens just to the east of
the Florida Peninsula. The local airmass surrounding the Keys will
remain moist and relatively unstable. By this weekend, the large area
of high pressure centered to our northeast weakens and then gets
displaced north/northeastward as lower pressure slides in from the
southeast towards the southeast coast of the United States. There is
good agreement between the GFS and ECMWF models in regards to
strength and movement of that system. This keeps the forecast
confidence on the low side in regards to the local conditions for the
Florida Keys, but we can expect at least isolated/slight chance of
showers, and it would not be surprising if this needs to be adjusted
up to scattered/chance of showers with accompanying thunderstorms for
the middle and later portions of the forecast cycle. This of course
includes the upcoming holiday weekend. Temperatures should remain at
or a couple of degrees above the seasonal average through every
period of this forecast.

&&

.MARINE...
Expect freshening mainly easterly breezes across all waters
surrounding the Florida Keys from tonight through at least Wednesday
night. High surface pressure settling off the southeast coast of the
United States will then get displaced to the north/northeast by this
weekend by an area of lower pressure transitioning towards the
southeast coast from the tropical Atlantic. A moderate mainly
easterly breeze will continue through the middle and later periods
of the forecast.

&&

.AVIATION...
Expect VFR conditions through 00Z with east winds 5-10 knots. Will
place VCSH in the TAFs beginning 00Z with scattered development
expected.  Difficult to put exact timing on any impacts to the
terminals.  East winds 10-15 knots expected Wednesday with some
higher gusts.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  79  87  78  87 / 20 20 20 20
Marathon  78  89  79  89 / 20 20 20 20

&&

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

&&

$$

PUBLIC/MARINE.........04
AVIATION/NOWCASTS.....MM
DATA COLLECTION.......Fling

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000
FXUS62 KKEY 241459
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
1059 AM EDT TUE MAY 24 2016

.DISCUSSION...
A few pockets of showers with embedded thunderstorms earlier this
morning weakened and eventually dissipated on the north and south
sides of the middle and upper keys. Since then...any small echoes
that have sprouted on KBYX doppler radar have not sustained
themselves. Winds continue to turn to the east as high surface
pressure is shifting towards the Carolina coast and across northern
Florida.

The early morning local sounding shows a shallow layer of
easterlies, extending to about 3000 feet. We are moist and
conditionally unstable. Any convective resistance in the lowest
levels should be easily overcome for shower and thunderstorm development
through the afternoon. But we could use some triggers. That doesn`t
mean they don`t exist as a mid to upper level trough swings to our
east. But, a 30 percent chance of measurable precipitation looks
good for any focus that shifts across the area. A recent zone
forecast update made only a small adjustment to the initial
winds...basically setting them to east. The remainder of the sensible
forecast elements were advertised well from the early morning
issuance.

&&

.MARINE...
As with the zones, the only change to the recent coastal forecast was
to set the initial wind conditions to the east/north for most of the
waters surrounding the Florida Keys. Expect freshening conditions as
the high surface pressure settles off the Carolina coast tonight
through Wednesday.

&&

.AVIATION...
Expect VFR conditions through most of the day with east winds 5-10
knots. Will place VCSH in the TAFs beginning 21Z with additional
scattered development expected.  Difficult to put exact timing on
any impacts to the terminals.  Light east winds will continue
tonight with scattered deck around 2500 feet.

&&

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

&&

$$

PUBLIC/MARINE.........04
AVIATION/NOWCASTS.....MM
DATA COLLECTION.......Vickery

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