Area Forecast Discussion
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FXUS62 KKEY 151836

Area Forecast Discussion
National Weather Service Key West FL
236 PM EDT Tue Oct 15 2019

Water vapor imagery highlights a mean layer ridge over the Gulf of
Mexico which measured 592 dm at 500 mb on this morning`s KKEY
RAOB. High pressure persists over the eastern United States and
Florida, which supports moderate easterly breezes across the
coastal waters of the Florida Keys. Temperatures are in the mid to
upper 80s with dewpoints in the mid 70s. Suppression aloft, low
level inhibition, and decreased lower tropospheric moisture has
resulted in a sunny, rain-free day across the Florida Keys.

A potent short wave over the northern Plains will pivot to the
southeast tonight, carving lower heights across the southeastern
United States. The low level ridge axis will cede territory to the
developing storm system over the east, and will be across the Keys
Wednesday morning. On Wednesday and Wednesday night, a short wave
over Texas will battle the mean-layer ridge over the Gulf, shoving
it to the southeast to near Cuba. Baroclinic forcing will act upon
festering tropical moisture over the Bay of Campeche on Thursday
and Thursday night, dragging a sloppy and elongated area of low
pressure northeastward toward the northern Gulf Coast. Despite all
this action over the Gulf and the eastern United States, the Keys
will feature slim rain chances and light breezes. Isallobaric
forcing Friday through Saturday night will result in freshening
southeasterly breezes and increased rain chances. By Sunday, the
subtropical ridge will build across Florida, lending to gentle to
moderate east-southeasterly breezes Sunday night through Monday
night. Although this is a long range forecast, we will be
watching for a dying cold front over the Florida Peninsula
sometime around next Tuesday. These harbinger fronts rarely punch
through our latitude, and yet it`s still a sign of things to
come. For meteorologists, October is like kids waiting for the
holidays. The artic refrigerator is on, and winter is coming.


No current watches, warnings, or advisories. From synopsis, high
pressure over the western North Atlantic will maintain gentle to
moderate easterly breezes across the coastal waters of the Florida
Keys this evening. The ridge axis will shift southward across the
Keys late tonight through Thursday night, lending to light
breezes. An area of low pressure will move north to northeast
through the west- central Gulf of Mexico Friday through Saturday.


VFR conditions are expected at both island terminals for the rest of
the afternoon and evening. With substantial dry air in place, only
anticipating a few passing cumulus clouds over the island chain
through 06z. Easterly winds at 7 to 10 knots will gradually veer to
southeasterly and decrease late this evening.


October is a transition month for the Florida Keys in terms of
temperature.  For example, the average high temperature for Key West
on October 1st is 87 degrees; in contrast, the average high
at the end of the month on October 31st is only 82 degrees.


Key West  77  88  77  88 / 10 10 10 10
Marathon  77  90  77  90 / 10 10 10 10


FL...Coastal Flood Advisory for FLZ076-077.



Data Collection......KBL

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