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fxus61 kctp 230344 
afdctp

Area forecast discussion
National Weather Service State College PA
1044 PM EST Wed Nov 22 2017

Synopsis...
high pressure will build into the area and last through the
weekend. Another cold front will push through Pennsylvania on
Saturday. A very dry period is in store through the beginning of
December.

&&

Near term /until 8 am Thursday morning/...
nighttime microphysics goes16 images showing medium-sized
breaks in the clouds over places east of unv, and mostly clear in
Adams/York/Lancaster counties. However, the western Highlands
are still stuck in the stratocu. Shouldn't be any more flurries
through the night. Otherwise, it should be a fair night with the
wind dying down as the pressure gradient relaxes.

Prev...
clouds are not going anywhere. The NAM seems to be doing well
with this trend - so far. There may not be any clearing over the
Allegheny Mountains until very late tonight, if at all. Some
clearing over the far eastern end of le and wrn New York is an
indication that the outlook is not all dismal, as the subsidence
must be winning there. However, the NAM does have this slot of
more-dry sky, and it closes it back up for the most part -
leaving only a thin slot running thru ipt later this
evening/early tonight. Temps may stay up in the northwest where
clearing is unlikely. But, that is also the location of the
thermal trough, and it may be tough to keep bfd from falling 7
more degs f overnight.

Prev..
still a few sprinkles and flurries occurring downwind of the
glaks this afternoon, but with inversion heights lowering
rapidly and high pressure nosing in, the duration and intensity
of lingering snow showers into this evening will limit accums to
additional trace to coating amounts over portions of the
northwest mountains.

By this evening, any lingering snow showers/flurries across the
northwest mountains should end, as the surface ridge axis
builds into the area. Clearing skies and diminishing winds will
allow temps to fall below seasonal norms, with readings mostly
in the low to mid 20s by dawn.

&&

Short term /8 am Thursday morning through 6 PM Thursday/...
high pressure at the surface will ensure dry weather and light
wind for Thanksgiving...despite passage of upper front which
will bring an increase of mid and high level clouds especially
in the afternoon hours. Max temps should range from the mid 30s
over the northwest mountains, to the low 40s in the susq
valley.

&&

Long term /Thursday night through Wednesday/...
high confidence of fair and seasonable weather Thursday night
into Friday, as all guidance continues to indicate weak ridging
aloft in advance of next system. Expect a somewhat milder day
Friday, as surface high passes off the coast and return
southwest flow ensues.

Relatively good agreement among Med range guidance into Sat/sun,
with a cold front passage likely midday Saturday after a mild
Fri night. Scattered rain showers will likely accompany the
front on Sat, followed by a period of lake effect snow showers
Sat night into Sunday, as another blast of seasonably chilly air
charges across the relatively mild waters of the grt lks. Ecens
and gefs both support below normal temperatures Sunday, as deep
upper level trough swings over the northeast states.

All signs are pointing toward fair and milder weather early
next week, as upper ridging is progged along the eastern
Seaboard in all Med range guidance. The guidance diverges by
midweek with GFS bringing a cold front and deeper trough
through, while the ec splits the energy off into a closed low
that remains back over the central U.S.

&&

Aviation /04z Thursday through Monday/...
no real change to the 03z tafs.

Clouds still holding tight across the mountains.

Some lower clouds will be across the mountains at times into
Thursday morning. Otherwise VFR conditions will prevail into
Friday, as high pressure builds into the area.

Brisk winds will prevail at times early on.

Overall pattern favors no big weather systems into the upcoming
weekend and into early next week, but frontal passages with
limited moisture every few days.

Have a good Thanksgiving.

Outlook...

Fri...no sig wx expected.

Sat...chance of rain/snow showers.

Sun...chance of snow showers across the northwest in the morning.
Otherwise no sig wx expected.

Mon...no sig wx.

&&

Ctp watches/warnings/advisories...
none.

&&

$$

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