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Area forecast discussion...updated 
National Weather Service Miami Florida
753 PM EDT sun Jul 13 2014

Update...
the showers and thunderstorms that have been occurring over the
interior and West Coast metropolitan areas have dissipated this
evening...as drier air has worked into the area from the Atlantic
waters. The drier air will remain in place over South Florida
tonight keeping most of South Florida dry. The only exception to
this is for a few showers that could work into the East Coast
metropolitan areas late tonight into early Monday morning from the
Atlantic waters on the easterly wind flow. So will keep a slight
chance of showers in the the forecast for the East Coast metropolitan
areas for late tonight into early Monday morning while removing
the probability of precipitation over rest of South Florida.

&&
Aviation...
VFR will prevail through the period. Little if any rain showers/thunderstorms and rain are
expected overnight...and thunderstorms and rain are expected to remain focused
interior on Monday. Only assigned thunderstorms in the vicinity to kapf Monday afternoon. Light
winds will increase to near 10 knots out of the southeast Monday afternoon East
Coast and SW at kapf.

&&
Update..54/bnb
aviation...gregoria



Previous discussion... /issued 154 PM EDT sun Jul 13 2014/

Short term...(tonight-Tuesday night)

The latest numerical model guidance continues to support an
amplifying upper pattern developing across the country through the
upcoming few days that will be characterized by a deepening trough
across the eastern states with several pulses of energy translating
through its base across the region. This will push a cold front
southward into the region and will lead to the subtropical ridge
axis weakening and shifting over and just south of the local area by
Wednesday. Monday night through Tuesday appears to be a transition
period for South Florida as the mean low-level ridge axis shifts
over the area and the low-level flow shifts from the southeast to
south-southwest. This pattern will likely lead to one more day with
the afternoon/evening showers/thunderstorms setting up over the interior and
West Coast on Monday...before shifting back toward the interior and
East Coast Tuesday afternoon/evening as the flow shifts. The
guidance reflects this and indicates a west to east precipitable water gradient
with the highest precipitable waters over the western half of the peninsula Monday
and over the eastern half by Tuesday evening. A combination of weak
steering flow...daytime heating and plenty of deep layer moisture
will support mainly sea breeze/outflow driven activity each day. The
latest guidance also supports slightly steeper middle-level lapse rates
by Tuesday afternoon with 500 mb temperatures projected to dip into
the 8-8.5 degree c range...which could support stronger afternoon
thunderstorms.

85/ag

Long term...(wednesday-saturday)

The trough will linger over the northeast U.S. Through the end of
the week with weak steering flow across South Florida as a deep
layer ridge remains in the area. The trough will lift to the east by
next weekend with the ridge shifting back to the north. This will
return a deep easterly flow pattern for South Florida with storm
development once again favoring the interior and West Coast regions.

30/kob

Aviation...

All East Coast terminals assigned thunderstorms in the vicinity at 18z with activity thus far
in the eastern portions of the peninsula but remaining to the west
of the terminals. The forecast and latest model guidance continues
to indicate that additional convection after 18z should start to
shift westward into the interior and western peninsula as the West
Coast sea breeze becomes more established with terminal kapf
assigned thunderstorms in the vicinity at 19z. Terminal kapf may experience brief periods of
MVFR to near IFR conditions with the occurrence of
showers/thunderstorms.

60/blowing dust

Marine...

Light to moderate southeasterly winds south of high pressure will
continue into the beginning of the upcoming week. Winds will shift
toward the south through the middle-week period as a cold front enters
the region and high pressure shifts south over the local area. Winds
and seas may become locally higher in and around heavy showers and
thunderstorms that develop each day.

&&

Preliminary point temps/pops...
West Palm Beach 77 88 78 90 / 20 20 20 30
Fort Lauderdale 80 90 81 90 / 20 20 20 30
Miami 78 90 79 90 / 20 20 20 30
Naples 75 91 75 90 / 20 40 20 30

&&

Mfl watches/warnings/advisories...
Florida...none.
Am...none.
GM...none.
&&

$$

Short term...54/bnb
long term....85/ag

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