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Area forecast discussion...updated 
National Weather Service Miami Florida
443 PM EDT Sat Sep 20 2014

most of the showers and thunderstorms that been occurring over the
eastern areas of South Florida have pushed into the Atlantic
waters late this afternoon. The only area that could still see
some showers and thunderstorms is over Miami-Dade County as this
area has not been work over yet today. Therefore...the probability of precipitation have
been lowered over most of South Florida...except for the southeast
areas of South Florida where scattered probability of precipitation will remain in place
for this afternoon. For the Atlantic waters...the probability of precipitation have also
been raised to numerous coverage for the on going shower and
thunderstorm activity.

Rest of the forecast looks good at this time and no other changes
are planned.


Previous discussion... /issued 326 PM EDT Sat Sep 20 2014/

the sun came out this afternoon across the southeastern portion of
the region...and temperatures were able to get briefly into the
upper 80s to around 90 degrees. Showers and storms were beginning
to fill in across the East Coast metropolitan areas...and numerous to
widespread showers and isolated/scattered storms will continue
across South Florida through the afternoon hours. The main threat
this afternoon will be locally heavy rainfall and isolated street
flooding for the East Coast metros. Gusty winds up to 50 miles per hour are
also possible.

Tonight...showers and storms will diminish slowly this evening
with loss of daytime heating...but redevelopment is possible
overnight for the Gulf waters through the Naples region. The area
of low pressure off the East Coast of North Florida will move
northeast overnight...but the frontal boundary across central
Florida will remain stationary.

Sunday and Monday...deep moisture will remain across South
Florida to the south of the boundary across central Florida...with
precipitable waters around 2 inches. Weak upper troughing will also continue
across the region. A few middle level impulses slightly detached
from the parent 500mb shortwave well to the north are expected to
slide to the northeast across the northern interior. This should
enhance thunderstorm development over the area for through the
beginning of next week. Numerous showers and storms are expected
each afternoon.

A more easterly flow pattern returns Tuesday and should persist
through the remainder of the week as middle level ridging becomes
firmly entrenched across the western Atlantic. Chances for showers
and thunderstorms will prevail each day with models depicting the
deep moisture axis remaining across South Florida. Model soundings
depict precipitable water values ranging between 1.75-2.00 inches through the
remainder of the week. The deep moisture and resultant cloud cover
along with an overall lack of dynamics should keep the strong to
severe thunderstorm potential limited.

scattered showers and storms associated with a frontal boundary
and upper trough will continue to develop and increase in
coverage across the area through the afternoon hours. West-southwest flow
will focus the heaviest activity toward the East Coast sites
through this time today. The flow should prove to be too strong
for the East Coast sea breeze to set up...which is reflected well in
the latest hrrr run that indicates the activity pushing through
and off the coast through the early evening period. VFR conditions
should return through the late evening and overnight hours with
light westerly flow continuing. 85/ag

general southwesterly winds at around 10 knots or less should
prevail through the weekend as an area of low pressure departs to
the northeast. A more easterly flow regime will then set up
through the first part of next week as high pressure returns
across the western Atlantic. Seas should remain at around 3 feet
or less.


Preliminary point temps/pops...
West Palm Beach 73 88 75 86 / 40 50 20 60
Fort Lauderdale 75 88 78 87 / 40 60 20 60
Miami 74 88 77 87 / 40 60 20 60
Naples 75 87 75 86 / 50 50 20 60


Mfl watches/warnings/advisories...


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

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