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000
FXUS61 KCTP 160314
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1114 PM EDT Tue Aug 15 2017

.SYNOPSIS...
A weak and almost exclusively dry cold front will drift south
across Central PA tonight before dissipating as a ridge of high
pressure builds in from the Great Lakes region. Seasonably warm
and dry conditions will occur Wednesday with abundant sunshine
and light wind. Mainly clear skies and comfortable temperatures
will follow for Wednesday night. Morning sunshine on Thursday
will fade behind increasing afternoon clouds as a warm front
approaches from the south, bringing some showers and
thunderstorms to the region mainly Thursday night. A cold front
will push through the state late Friday and Friday night
bringing with it a few round of showers and Thunderstorms.
High pressure will clear things out behind the front for the
weekend.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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Spooter reports indicate that vsbys across parts of our SE zones
(that receievd some mdt rainfall amouns over the past 36 hours)
are locally dense. Sfc obs alos show vsbys coming down fast from
near KRYT and KTHV east to KLNS. this prompted collaboration
with KLWX and KPHI and issuance of a Dense Fog Advisory for
several SE counties in our CWA from 03Z to 13Z Wed.

High res/CAMS guidance agrees well with regional radar mosaic
with respect to a subtle light wind shift line associated with a
very weak cool front dropping south across the nrn mtns of PA
this evening. Several, isolated showers were seen along this
boundary, but overall area POPs to the south of Interstate 80 will
stay mainly below 10 percent, while a few locations across the
NW and Ncent mtns will be in the high chc range.

After 05Z Thursday...rising heights and weak ridging aloft will
lead to continued drying with skies expected to become clear to
scattered. Light and variable winds and moderately high sfc
dewpoints ranging from the L60s NW to the L70s SE will likely
dip up to several deg late tonight via condensation/likely
valley fog formation

Overnight lows in the 50s and 60s will be several deg warmer
than normal.
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&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
Wednesday continues to look dry after starting the day with a
fair amount of fog to burn off. With plenty of sunshine we warm
into the 70s and low 80s.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
High pressure will remain over the region over the region into
Thursday. However the 00Z EC/GFS/NAM are in good agreement of
another 500 MB trough approaching the region through the Great
Lakes Thursday afternoon. This will correspond with a mid level
closed low that will move through the peninsula of Michigan and
bring a warm frontal boundary through the state Friday. This
will allow for higher Max temperatures and a better chance for
showers and thunderstorms Thursday night into Friday.
Models begin to diverge into the weekend bu they have a cold
front moving through the mid Atlantic Friday night into Saturday
morning. Based on NBM and latest mid range guidance have trended
temperatures upward.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
SERN zones continue to grudgingly improve as the rain moves off
to the east. Light winds assure improvement will remain slow as
no well defined push of dry air is expected. Elsewhere some weak
instability will lead to an some isolated pop up
showers/thunderstorm in a few spots for the remainder of the
afternoon. Briefly lower conditions could result if a terminal
takes a direct hit.

Fog is expected to redevelop overnight as clouds scattered out
and the wind remains light. impacts expected late tonight into
early Wednesday with some restrictions AOB airfield mins.

.OUTLOOK...

Thu-Fri...Sct Tstm impacts likely.

Sat...No sig wx.

Sun...Restrictions with scattered showers and thunderstorms.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
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Dense Fog Advisory until 9 AM EDT Wednesday for PAZ057-059-
063>066.
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&&

$$
SYNOPSIS...Lambert
NEAR TERM...Lambert
SHORT TERM...La Corte
LONG TERM...Ceru/Gartner
AVIATION...La Corte