Area Forecast Discussion Issued by NWS State College, PA
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FXUS61 KCTP 251904
AFDCTP
Area Forecast Discussion
National Weather Service State College PA
304 PM EDT Mon Mar 25 2024
.SYNOPSIS...
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A sunny and dry start to the week with seasonal temperatures
followed by clouds and periods of rain from Tuesday through
Thursday. Fair weather with brisk winds and slightly cooler
temperatures will close out the week on Friday.-- End Changed Discussion --
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.NEAR TERM /THROUGH TONIGHT/...
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1040mb high pressure centered over the Gulf of St. Lawrence
channeling southward along the eastern slopes of the
Appalachians will maintain dry wx in CPA through tonight.
Southeast wind gusts peak in the 35-45 mph range on the
ridgetops across the western and northern Alleghenies from late
this evening through tonight. We added some potential limited
wind impacts to the HWO, but will hold off on issuing an advisory
with the highest gusts more likely in the downslope areas in
PBZ`s CWA and closer to the Lake Erie shoreline.
Lows tonight in the 30-40F range will be within +/- 3F of climo
over the SE half of the CWA, to +5-10 deg F above normal over
the western and northern Alleghenies. HREF data continues to
indicate low clouds expanding into the lower Susquehanna Valley
into early Tuesday morning.-- End Changed Discussion --
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.SHORT TERM /TUESDAY THROUGH THURSDAY/...
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The aforementioned low clouds could expand as far west as the
I99 corridor by late Tuesday morning. The lower clouds will work
in underneath thickening mid and high clouds from the west and
result in a cloudy day tomorrow. The low clouds coupled with the
cool/moist southeast flow could hold temps back in the mid-
upper 40s on the east side of the Alleghenies - a scenario that
the NAM and other hires guidance is increasingly bullish - which
caused us to fade the NBM maxT by a few degrees for now.
A slow moving and weakening sfc cold/occluded front will slowly
push eastward across CPA through midweek. Periods of rain are
forecast with QPF amounts 0.10-0.25" through Wednesday. Max
temps are forecast to peak on Wednesday in the 50-60F range
bookended by relatively mild nights for late March.
Focus for rain should shift into southeast PA by Thursday as
wave of low pressure develops along the southeast coast. Trends
in the guidance have been for the low to track closer to the
coastline, which brings higher POPs and QPF into play over the
lower Susquehanna Valley/southeast PA. The latest WPC/NBM qpf
blend yields ~0.50" for areas to the southeast of I-81 Wed night
through Thursday, with heavier rain forecast farther to the
southeast.-- End Changed Discussion --
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.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
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All medium range guidance develops an area of low pressure on
the stalling front over the southeast coast, then tracks it
northeast late this week. The bulk of ensemble members keep this
system too far east to affect most of Central PA. However,
enough members track it close enough to support a chance of rain
over the southeast part of the forecast area Thursday. Plumes
indicate if it does rain, substantial amounts of near 1 inch are
possible.
There is a broad agreement among guidance that fair and
seasonable conditions return for Friday, as large scale
subsidence overspreads the state behind the exiting upper
trough. A weak wave of low pressure tracking across PA could
produce a bit of light rain or showers Sat or Sat night.-- End Changed Discussion --
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.AVIATION /18Z MONDAY THROUGH SATURDAY/...
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Widespread VFR conds will continue through evening and into
the first part of tonight/thru 06Z. Increasing southeasterly
low level flow tonight into early Tuesday will bring low clouds
into the southeast airspace with HREF indicating >70% of MVFR.
These clouds could make it as far west as AOO/UNV by late
Tuesday morning, but for now (given reduced confidence/~50%
probability) have kept cig height just above MVFR. LLWS 40-50kt
from 150-180 degrees is expected to impact the western
airfields 00-18Z Tuesday. A band of rain is forecast to reach
the western airspace by Tuesday evening and slowly push
eastward across the central and eastern airspace through
Thursday.
Outlook...
Tue...Increasing clouds areawide.
Tue night-Wed...Periods of rain with MVFR to IFR cigs.
Thu...Rain sub-VFR cigs possible S/E.
Thu night-Fri...MVFR cigs west. Wind gusts 20-30kt from 300
degrees.
Sat...Chance of rain mainly over the southwest airspace.-- End Changed Discussion --
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl
SHORT TERM...Steinbugl
LONG TERM...Fitzgerald
AVIATION...Steinbugl