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fxus61 kctp 230039 

Area forecast discussion
National Weather Service State College PA
839 PM EDT Tue Oct 22 2019

a cold front is moving across the region this afternoon bringing
with it a soaking rain to the area. This front will clear the
area this evening with decreasing showers and clearing skies.
This will leave the area with several nice days and seasonable


Near term /through Wednesday/...
830 PM update... band of moderate rain is now east of our
forecast area and continuing to move away. A few isolated
showers are located along a surface cold front, moving into
central PA this evening. However, as the better upper-level
support bypasses our region to the north overnight and the
moisture supply continues to dwindle with time, we think any
showers early this evening will quickly diminish. Thus, we'll
leave the current forecast in tact, which mentions little to no
shower activity going forward.

As partial clearing continues to work its way eastward across
central PA overnight, the combination of wet top soil and
decent radiating conditions will result in patchy development of
of lower clouds and fog. This also seems to be well handled with
our current forecast grids.

Given some low-level cold advection overnight, lows by daybreak
will range from the upper 30s over the northern mountains, to
the upper 40s in the lower Susquehanna valley.

Previous discussion... deep low level moisture just ahead of
frontal system is bringing a widespread area of moderate rain.
This much needed rainfall will begin to decrease from west to
east this afternoon as drier air approaches. This drier air will
bring rapid clearing this evening and with the longer nights
and ample low level moisture widespread fog development is
expected over the eastern half of the County Warning Area. Winds will be a bit
stronger over the west which will reduce fog formation.


Short term /Wednesday night through 6 PM Wednesday/...
high pressure strengthens over the region on Wednesday with
nearly full sunshine. Winds will be gusty out of the west. The
air behind the front is not very cool, so temperatures will
rebound back to seasonable norms during the afternoon.


Long term /Wednesday night through Tuesday/...
zonal flow at midweek delivers fair and milder conditions as
as high pressure passes off the mid Atlantic coast and a return
southwest flow develops. Medium range guidance is slower with an
approaching frontal system for Friday and Saturday, and still
substantially differ with rain chances and timing this weekend
of secondary low pressure over the Carolinas tracking off the
mid Atlantic coast Sat-Sunday. Stuck close to nbm chances with
bulk of rainfall remaining southeast of the area.

Med range model consensus supports milder but unsettled
conditions next week with chances for showers every 12-18 hours
as upper trof remains over the eastern third of the US.


Aviation /01z Wednesday through Sunday/...
steady rain is moving east of the forecast area with clearing
skies moving in behind. Expect conditions to improve to MVFR
through the evening hours; however, areas of patchy fog will
develop with rain soaked lower levels.

Expect brief drops to IFR and even LIFR over the elevated
airfields through the night time hours. High pressure will allow
for clearing around sunrise with good VFR to clear skies
dominating the region through most of the day on Wednesday.

Outlook... sig wx expected.

Fri...some showers possible, especially west late.

Sat...areas of low cigs early, otherwise mainly VFR.


Ctp watches/warnings/advisories...



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