Area Forecast Discussion
Issued by NWS Miami, FL

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FXUS62 KMFL 210027
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
727 PM EST Mon Nov 20 2017

.UPDATE...
Radar data shows showers now increasing across the Miami metro
area and around Homestead. Passing showers will continue to spread
across much of South Florida tonight as a stalled front over the
Keys gradually lifts back northward through Tuesday night. POPS/WX
have been updated to reflect greater coverage during the next 24
hours. Most rain should be stratiform in nature, thus accumulations
should remain around half an inch for the most part. Greater
accumulations could briefly happen with any thunderstorm that
forms, but the better chances for thunderstorm activity remain on
Tuesday afternoon.

The rest of the forecast package remains on track and no other
changes are required for the evening update.

&&

.PREV DISCUSSION... /issued 324 PM EST Mon Nov 20 2017/

DISCUSSION...
Short Term (Tonight-Wednesday)...model and satellite data depicts
a frontal boundary stalling just south of the Florida Keys, which
will keep mainly scattered showers across the southern tip of the
peninsula this evening, including the Atlantic metro areas. Winds
will gradually veer to more easterly flow and help in pushing the
remnants of the front again northward and across the area. This
will likely bring back showers over South Florida from southeast
to northwest later tonight. Shower activity will continue to shift
northward and into Palm Beach county and the Lake region by
Tuesday. Models also show a shortwave trough feature approaching
the state from the Gulf, which combined with lingering moisture
will keep chances for more showers and may even support a few
thunderstorms.

For Wednesday, models depict a drier air mass filtering into the
region as the remnant front dissipates further north of the area
and the shortwave departs to our east. This will translate into a
much drier day with very low chances of rain Wed afternoon.

Long Term (Wednesday night-Sunday): models insist in showing a
deepening mid level shortwave trough moving into the Gulf area,
which gradually approaches the state Thu-Fri. A series of low
level energy impulses, associated with the trough, will travel
across the area and bring increasing instability for showers and
increasing chances of thunderstorms Thursday through Friday afternoon.

For the weekend, models agree in bringing much drier air behind
the trough, resulting in clearing skies by Saturday and generally
benign weather for the rest of the weekend. Also, the cooler/drier
air mass will allow for temperatures to cool down, probably into
the lower 50s northwest to lower 60s southeast beaches by Sunday
morning.

MARINE...
NE winds around 20 knots are still persisting in the some of the
Atlantic waters, while winds on the Gulf side are gradually
diminishing. Winds over the Atlantic waters will veer around to
easterly, with hazardous boating conditions continuing tonight.
The fresh breeze will be accompanied by significant wave heights
of 7 feet or so in the Gulf Stream. Conditions improve Tuesday and
through the rest of the week, though scattered thunderstorms will
be possible Tuesday and again on Thursday into Friday.

BEACH FORECAST...
There will be a high risk of rip currents at the Atlantic Beaches
through Tuesday as onshore winds increase. Beachgoers must be
aware of the risk of rip currents and heed all warning messages.

AVIATION...
The cold front that came through this morning has stalled just
south of the Keys. This has kept enough instability near the area
to keep a few showers over the coastal waters, but has not been
enough to cause as much activity as previously thought. So, have
dropped mention of SHRA through the day. Models are still
indicating nocturnal activity tonight. VFR should be predominate,
but IFR will be possible, mainly due to CIGs, not too much
uncertainty as to occurrence and coverage to mention attm.
&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  70  82  66  83 /  60  60  30  20
Fort Lauderdale  72  83  70  84 /  60  50  20  20
Miami            71  84  69  85 /  60  50  20  20
Naples           67  82  66  83 /  20  30  20  10

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through Tuesday evening for FLZ168-172-173.

AM...Small Craft Advisory until 7 AM EST Tuesday for AMZ650-651-670-
     671.

GM...None.
&&

UPDATE...17/AR










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