Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 250548
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
148 AM EDT Wed Apr 25 2018

.SYNOPSIS...
A slow moving area of low pressure will produce periods of rain
into Wednesday. Expect dry but still cooler than normal
conditions on Thursday before a new disturbance moves our way
for Friday into Saturday.

Another stretch of fair weather will start Sunday along with
moderating temperatures.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
It took all day, but rain is finally falling over most of the
forecast area. The parent upper low is forecast to move to the
VA coast before opening up and being absorbed into a new trough
dropping out of SRN Canada and the GR Lakes.

It all translates to periods rain continuing overnight and
into Wednesday morning. The rain should become more scattered
and showery Wednesday afternoon, but true drying is not likely
until the trough axis passes perhaps as late as this time
tomorrow evening.

Overall, rain doesn`t look terribly heavy. Between 1/2 and 3/4
inch on average. It will be a chilly rain with lows tonight in
the 40s.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
Main area of precip will likely be from the deformation
zone/WCB circulation to the northwest of the deepening sfc low.
The low will pass right over NJ on Wed. As the low moves to the
north along the coast, dry air will get pulled in from the NW.
The rain should be tapering off in the east during Wed AM.

Some SHRA develop over the NW and western elevations thanks to
a ill-timed upper trough, but the SE half of the area should
begin to dry out nicely. The NW should dry out Wed evening.
The downslope and extra sun will help the SE get into the 60s,
but the rest of the area will be in the 50s in the afternoon
without much sun.

Cooler Wed night with improving conditions as lows slip into the
30s over the western/northern elevations and in the 40s
elsewhere.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Rain showers should end by early Thursday with the rest of the
day likely staying dry. The best opportunity for widespread rain
looks like Thursday night into Friday as wave of low pressure
tracks north from the Southeast. Models continue to differ on
how developed the system will be with ECMWF remaining one of the
weakest and more suppressed solutions. The main upper level
trough/cool air aloft may produce showers Friday night into
Saturday before conditions dry out by the second half of the
weekend.

Despite a late start to the growing season, there will be a
frost/freeze risk Monday morning.

Model data supports a pattern change toward troughing in the
Western U.S. with ridging indicated from the Plains eastward.
A developing Bermuda high surface pattern with mild SW return
flow should boost temperatures above average by early next week.
Temperatures will trend notably warmer with readings in the
70s/approaching 80F in some locations by next Tuesday.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Still showers to the east, less to the west. Could be a rumble
of thunder across the southeast, left out of the LNS and MDT
TAFS for now.

06Z TAFS sent.

Earlier discussion below.

Latest Radar showers widespread light showers moving northward
and overspreading the region. Currently, JST has dropped to IFR
with MVFR at BFD, MDT, LNS and AOO. However all sites are expected
to continue to deteriorate between 03Z to 06Z with widespread
IFR across all TAF sites between 06Z to 13Z.

Conditions improve starting over the southern mountains and Susq
Valley on Wed as flow turns to the west and downslope begins to
dry out the lower layers. But an upper trough slides in
reinforcing clouds over the NW half and brings scattered
showers. So MVFR is still expected through Wednesday afternoon.

Outlook...

Thu...AM low cigs possible W Mtns.

Fri...Areas of rain with low cigs etc.

Sat...AM showers/cig reductions possible NW Mtns.

Sun...Reductions possible NW Mtns.

&&

.CLIMATE...
April 2018 currently ranks in the top 10 coldest on record
through the 23nd. Seasonable temperatures are expected through
the end of the month followed by a significant warmup into early
May.

&&

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

&&

$$
SYNOPSIS...La Corte/RXR
NEAR TERM...La Corte/RXR
SHORT TERM...RXR
LONG TERM...Steinbugl
AVIATION...Ceru/Martin
CLIMATE...Steinbugl



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