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000 
FXUS62 KMFL 100558
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
1258 AM EST Sat Dec 10 2016

.AVIATION...
Showers continue intermittently along the east coast, including
the east coast terminals, and expect this to continue for duration
of the TAF period. Heaviest showers occurring over PBI as of 6z,
and thus MVFR TEMPO group in place there for next 4 hours. Similar
situations could evolve today at other terminals, but confidence
too low to include in forecast attm. NNW wind 5-10 KT overnight
will increase by late morning to 15-20 KT out of the NE. Gusts
could approach 30 KT at times this afternoon.

&&

.PREV DISCUSSION... /issued 752 PM EST Fri Dec 9 2016/ 

UPDATE...Winds have decoupled in a few places along the east
coast, setting up light drainage flow and backing winds a little 
more northwest. This has allowed temperatures this evening to 
drop more quickly than expected. 

Winds above the surface however remain NE, which will bring some
of the lower clouds and showers into the coast with time.
Initially, we will likely see a case where winds may oscillate 
between NNW and NNE with temperatures changing a few degrees with 
each swing. However, expect winds to become more definitively NNE
to NE, at least for the immediate east coast as showers and 
clouds move in. 

No significant changes to the pop forecast, but will adjust
overnight lows to match current trends. 

PREV DISCUSSION... /issued 434 PM EST Fri Dec 9 2016/ 

DISCUSSION...

This afternoon-Tonight: While the main surface front has passed 
through the Florida Straits, we remain in a lingering area of deep
tropical moisture lying across the FL peninsula from about Lake 
Okeechobee southwards. This has lead to a rather gray, cooler, and
occasionally drizzly day for South Florida. 

Models show a weak convergence boundary setting up over the
Atlantic this evening and overnight as flow veers more NE. This
will help bring more of the ongoing activity over the Atlantic
into the east coast overnight, with rain chances around 40-50%.
The remainder of the interior and Gulf coast may see
drizzle/sprinkle at times. While much deep convection isn't 
expected, will have to monitor for potential training of showers
into the east coast but light to moderate activity will generally
be the order of the evening. 

While the Arctic air associated with the strong high pressure over
the Midwest won't reach us in South Florida, as the high builds
south we will see breezy conditions continuing through the
overnight hours and more seasonable overnight lows continuing.

This Weekend: Cloudy and breezy sums up the weekend across the
region as the aforementioned high continues to sink south and east
across the Deep South and into the Atlantic. Deeper moisture and
lingering weak low level boundaries will continue to bring scattered
showers into the east coast, occasionally reaching into the 
interior and Gulf coast. Temperatures will be around normal in 
the mid-upper 70s on Sat, before warming into the upper 70s and 
low 80s on Sunday. The breezy conditions will also keep overnight 
lows relatively mild in the upper 50s and low 60s for the interior
and Gulf coast and upper 60s/low 70s for the east coast, warming 
further Sunday night.

Next Week: While the large scale pattern across the remainder of 
the continental US remains fairly progressive, South Florida looks
to remain under the influence of weak high pressure off to our 
north and east through at least mid week. We will remain in a 
fairly moist environment under lighter low level southeasterly 
and mid level southwesterly flow, bringing widely scattered 
showers across the region, especially for the east coast metro.
This wind flow will keep temperatures near to slightly above 
normal for mid-December.

MARINE...Hazardous marine conditions will be in place across the
local Gulf and Atlantic waters through the weekend.

Gusty northeasterly flow ha already overspread the region behind
the cold front with winds around 20 knots with occasional gusts to
25 knots. While this looks to be the general forecast for the
upcoming weekend, there will be a period of 20-25 knots late 
Saturday into Sunday morning with the potential for occasional 
gale force gusts over the Atlantic as high pressure builds further
east. This will drive choppy seas around 7-9ft over the Atlantic
and 5-7ft in the offshore Gulf waters. 

Winds veer easterly by Sunday, before diminishing and coming
around to the southeast on Monday as the surface high weakens and
moves into the Atlantic to our north. Marine conditions look to
improve by Monday afternoon with a more benign wind and sea 
forecast into mid week. 

BEACH FORECAST...A more northerly wind component has held the 
Atlantic rip current risk at moderate today with a notable
longshore current. However, expect a high risk over the weekend as
winds become east-northeast and very gusty. The threat for 
dangerous rip currents will likely linger into early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  75  69  80  72 /  50  30  30  40 
Fort Lauderdale  75  70  79  73 /  50  40  40  50 
Miami            77  69  80  73 /  50  40  40  40 
Naples           78  63  83  68 /  10  10  10  10 

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory until 4 PM EST this afternoon for AMZ630-
     650-651-670-671.

GM...Small Craft Advisory until 4 PM EST this afternoon for GMZ656-
     657-676.

&&

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