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Area Forecast Discussion (AFD)

Issued by State College, PA (CTP)

                            
000
FXUS61 KCTP 160044
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
844 PM EDT Sun Sep 15 2019

.SYNOPSIS...

High pressure will build to our north through Monday. Meanwhile
a weak warm front will approach from the Midwest. 

High pressure will return for Tuesday and usher in several days
of dry weather with temperatures at or above normal.

&&

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

The large scale pattern shows us under the NW flow on the east
side of a burly upper high over the Miss Valley. On the surface
a weak wave of low pressure will drop out of the lower lakes 
and drag a weak frontal system through the forecast area tonight
and Monday.

This should keep clouds over the region along with the chance 
of a few light showers or sprinkles that should confine
themselves mainly north of I-80. QPF will remain light,
generally a tenth of an inch or less. 

Mins temps in the u50s to m60s will be much above normal, 
thanks to the blanketing effect of the clouds.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
Weak area of sfc low pressure will cross the area on Monday, 
generating scattered showers across the NW mtns in the morning,
and more numerous small/brief afternoon showers elsewhere 
(though the actual areal coverage will be scattered). Many of 
these probably won't make it SE of the I-81 corridor. 

Maxes will range from 70F across the far north (north of the 
warm/quasi-stnry from) to the mid and upper 70s throughout much 
of Central PA, and low-mid 80s in the Lower Susq Valley.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
The weakening cold front could have just enough moisture Monday
evening to continue showers through the Laurels. That moisture
will dry up as a large upper level ridge will build over the
Great Lakes which will dominate the weather pattern through the
week.
This should keep central PA generally dry through the week. 
After a brief cool down behind the departing cold front, 
temperatures should slowly begin to moderate later in the week.

&&

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
A weak area of low pressure approaching from the midwest will
spread mid level cloudiness across central Pa tonight with a
light rain shower possible over the northern part of the state.
Model soundings and latest SREF probability charts support
widespread VFR conditions tonight. However, if clouds thin
enough, a period of fog is possible around dawn at KIPT, as the
latest LAMP and NAMNest indicate. 

The weak low pressure and trailing cold front will slide across
the region on Monday, accompanied by scattered showers. VFR
conditions should prevail Monday for much of the region.
However, post-frontal, low level moisture combined with
orographic lift is likely to result in MVFR cigs during the PM 
hours across the northern mountains. 

.Outlook...

Tue-Fri...AM valley fog possible central/northern PA.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

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