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000 
FXUS61 KCTP 190230
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1030 PM EDT Fri Oct 18 2019

.SYNOPSIS...
High pressure will build into the region tonight with light
winds and clear skies. Temperatures will begin to moderate to 
above normal later in the weekend and into early next week. 
Rain associated with Tropical Storm Nestor may clip southern 
parts of the region on Sunday, but the best chance for a more 
widespread rain looks like it will not be until Monday night and
Tuesday.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...

Some fog is starting to show up in the valleys of western PA.
Other than some thin high clouds, there are no other clouds as
of late evening.

Surface high pressure will continue to build into the region 
from the west, providing nearly perfect radiational cooling 
conditions overnight. With light winds and clear skies, many
areas will see frost or even a freeze leading to the current
configuration of Frost/Freeze headlines for the parts of the 
forecast area where the growing season is still active.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
Saturday looks like lots of sunshine, a light SE wind 
developing, and temperatures rebounding to nearly normal. 
Perfect for outdoor activities, esp leaf peeping. Foliage seems 
to be near peak here locally, but lots of leaves just got blown 
down Thurs.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Clouds will increase Saturday night into Sunday to the north of
Tropical Storm Nestor forecast to track through the Deep South 
and then off the NC coast. The main forecast question remains 
if/how far north? precipitation can reach into central PA early
Sunday. A blend of the HREF and NBM support increasing precip
probs to around 60% across the far southern tier zones along the
PA/MD border. Light rain should exit the CWA Sunday evening
followed by clearing under high pressure Sunday night into 
Monday.

Ribbon of anomalous PWATs ahead of next frontal system will
likely bring moderate rain to the sometime between Monday night
Tuesday night. GFS is faster vs. ECMWF so a compromise is
favored for timing. Latest model trends indicate a more 
progressive system which would keep rainfall amounts somewhat 
in-check. The best chance for heavy rain (prob of 1"/12hr) is 
focused over the eastern 1/2 to 1/3 of the CWA. Mainly dry 
weather should follow for mid to late week. 

Blocking high over Greenland seems to allow for a potentially
stronger system to evolve over the Eastern U.S. next weekend.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
High pressure will build into the region overnight Friday with
mostly clear skies prevailing through Saturday. Winds will
become calm tonight with patchy fog possible Saturday morning,
mainly in the common valley locations. Cirrus associated with 
the Tropical Storm Nestor will begin to stream into southern 
Pennsylvania by Saturday afternoon and winds will turn and come 
out of the south.

.Outlook...

Sun...Light rain possible over southern PA.

Mon...AM valley fog possible. 

Tue...Rain/low cigs possible.

Wed...Rain showers/low cigs possible mainly AM. Improving PM.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 2 AM to 8 AM EDT Saturday for PAZ028-045-
046-049>053-056>059-063>066.
Freeze Warning from 2 AM to 8 AM EDT Saturday for PAZ019-
025>027-034>036.

&&

$$
SYNOPSIS...La Corte

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