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fxus62 kmfl 081743 aac 
afdmfl

Area forecast discussion...updated
National Weather Service Miami Florida
1243 PM EST Thu Dec 8 2016

Aviation...
light winds over the East Coast taf sites should become northeast
and increase to 5 to 10 knots by 19/20z this afternoon. The winds
will then decrease to around 5 knots tonight and become more
northerly in direction over the East Coast taf sites. Kapf taf
site will be northwest at 5 to 10 knots this afternoon before
going northeast around 5 knots tonight.

Isolated to scattered showers should continue to affect the East
Coast taf sites through 00z tonight. At this time, the short range
models are showing dry conditions at all of the taf sites.
Therefore, vcsh will remain in the forecast at all of the East
Coast taf sites through 00z, as kapf taf site will remain dry this
afternoon into tonight.

The ceiling and vis should remain in the VFR conditions this
afternoon into tonight at all of South Florida taf sites.
However, the ceiling and vis could fall down into MVFR conditions
with any passage of showers over the East Coast taf sites.

&&
Aviation...54/bnb



Previous discussion... /issued 911 am EST Thu Dec 8 2016/

Update...
the patchy to areas of fog that been occurring over the interior
and East Coast Metro areas early this morning should burn off in
the next hour or two, as heating continues over South Florida.

A stationary front will remain over the southern areas of South
Florida today, while a cold front over central Florida moves southward
and through South Florida by this evening. There is also a mid
level short wave over the southeastern Gulf of Mexico that will
move northeast today across the southern sections of South
Florida. This weather pattern will keep the tropical moisture in
place over South Florida today allowing for isolated to scattered
showers to develop over the area. There could even be a
thunderstorm or two over the southeastern areas of South Florida
this afternoon, due to the mid level short wave moving over this
area. Therefore, pops will range from 20 percent over the western
areas to 30 to 50 percent over the eastern areas of South Florida
this afternoon.

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

Update...54/bnb
&&



Previous discussion... /issued 639 am EST Thu Dec 8 2016/

Aviation...
most of the shower activity that impacted the southeastern
terminals has moved offshore through the early morning hrs.
A few streamer showers could develop near the terminal but
after mid day with daytime heating. Early this morning the
main concern will be the patchy areas of fog with vis between 1 to
3 miles in some of the East Coast terminals. Expect the low vis
to remain through early morning hours burning off with sunrise.
Northerly flow will prevail through the day with VFR conditions.

&&



Previous discussion... /issued 433 am EST Thu Dec 8 2016/

Discussion...
short term (today-saturday)...after an active night across the
area in terms of showers, expect additional scattered showers today
as the remnants of a stalled front remain in place over extreme
South Florida through Friday. Abundant low level moisture will
combine with daytime heating and possible sea breeze/onshore flow
to generate a few thunderstorms this afternoon. Higher chances of
rain will reside over the East Coast areas. The influence of the
boundary will also keep pressure gradients relatively light over
the southern half of the Florida Peninsula and keep winds light to
moderate from the north-northeast.

Models remain poised in showing building high pressure with strong
cold air advection across the eastern half of the nation, reaching
southern Florida by early Friday. This cold and drier air mass
will push the lingering tropical moisture southward Friday,
although a few showers are still possible in the afternoon hours.
Pressure gradients will become tighter, with increasing NE flow
bringing breezy to windy periods during the weekend.

The colder air will bring down temperatures to around 50 over
interior and Gulf areas Friday night, and low to mid 60s elsewhere.
Afternoon highs will remain in the upper 60s to low 70s on Friday,
and warm up back into the mid 70s by Saturday.

Long term (saturday night-wednesday)...the high pressure will keep
drier conditions on Sunday with low-end probability of precipitation remaining in the forecast
Sunday afternoon, mainly around the Atlantic coast Metro areas.
Models show some low level moisture filtering back into the area
on Monday with better chances for scattered showers in the afternoon
hours. Similar scenario is expected on Tuesday.

Models depict a cold front boundary approaching the region late
Tuesday, which may bring increasing chances of showers on Wednesday.

Marine...
the current light to moderate winds will keep seas around 2 feet
over the coastal waters today, then an approaching cold front
brings increasing northerly flow later tonight and into Friday.
Winds during the weekend could reach 20 knots at times with seas
reaching the 7 to 10 feet range, especially over the Atlantic
waters. Gulf waters could see seas building to 6 to 8 feet on
Friday before falling below 7 feet during the rest of the weekend.

Aviation... showers have developed over the southeast Metro
areas especially impacting sites from fll south. Expect brief
periods of moderate to heavy rainfall reducing vis to 2 miles or
less as the storms move through fll, mia and tmb. This is also
causing ceilings to lower to MVFR to IFR with the showers moving
by. No lightning has been observed with this activity but an
occasional lightning can not be ruled out. Fog/stratus may be a
concern over interior away from taf sites, but at the moment all
sites look to remain to be VFR with the exception of the storms to
the south. Next front comes in tomorrow afternoon with vcsh for
all sites after 15z. Winds remain light/vrb, becoming more north-northeast
with time behind front.
&&

Preliminary point temps/pops...
West Palm Beach 66 73 67 75 / 30 50 50 50
Fort Lauderdale 68 74 66 74 / 30 40 60 50
Miami 69 74 65 75 / 30 40 60 50
Naples 62 68 60 76 / 30 30 10 10

&&

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

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