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Latest PA Weather Summary:

931
AWUS81 KCTP 202346
RWSCTP
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-
049>053-056>059-063>066-211400-

Regional Weather Summary
National Weather Service State College PA
646 PM EST Wed Nov 20 2024

A strong cold front is moving eastward across the Commonwealth
this evening, bringing about a line of gusty showers with gusty
winds behind the front. A Wind Advisory is in effect for much of
southern Pennsylvania east of the Allegheny Front until early
Thursday morning.Dry conditions are expected after the line of
showers overnight, with low temperatures ranging from the lower
30s to the mid-40s.

Colder weather is likely for Pennsylvania on Thursday and into
the weekend in the wake of the cold front. Precipitation chances
increase across western Pennsylvania during the early morning
hours and continue overspreading the Keystone State. Snow showers
are expected across higher elevation locations all day Thursday
with a rain/snow mix possible across lower elevation locations
late Thursday evening into Friday morning. High temperatures on
Thursday will range from the mid-30s across the Laurel Highlands
to near 50 in the Lower Susquehanna Valley, with low temperatures
into Friday morning ranging from the lower 20s to the lower 30s.

Lingering snow showers are expected for the higher elevations
through Saturday, before warming temperatures will bring about a
transition to rain. Drier conditions are expected to prevail
across eastern Pennsylvania late Saturday into Sunday morning.

$$

Beaty

Latest Forecaster's Discussion:

252
FXUS61 KCTP 210555
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1255 AM EST Thu Nov 21 2024

.SYNOPSIS...
*A large area of rain over the eastern half of Pennsylvania will
move very slowly to the east overnight as surface low pressure
begins to strengthen near the New Jersey Coast as colder air
filters in changing the rain to snow over the higher terrain
toward daybreak Thursday

*Big pattern change in store for Thursday and Friday
associated with the first winter storm of the season

*Heavy, elevation-driven wet snow accumulation possible in the
Laurel Highlands and Poconos Thursday night-Friday night

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Moderately strong westerly wind gusts peaking in the 30s (KTS)
will continue for the next 2 to 3 hours before subsiding as the
main pressure rise/fall couplet accompanying the Cfropa shifts
toward the Mid Atlantic Coast. A Wind Advisory is in effect for
roughly the southern half of the CWA through 06Z Thursday.

Slowing eastward progression of the stratiform precip area
lagging the Cfropa for 23 hours will gradually pivot to become
more NW/SE oriented as the lead shortwave rotates to the eastern
side of the digging upper low heading at CPA from the Glakes
Region.

A few hours period of lighter stratiform rain diminishing to a
few showers along with decreasing wind becoming southwesterly
in direction will follow for the middle of the overnight, then
some clearing an light wind will occur later tonight (West)
through the mid morning (across the East).

As we approach day break tomorrow a few wet snow flakes begin
to fly around on the highest ridges of Laurel highlands and
Western Poconos/Endless Mtns Region of NEPA. The heaviest
snowfalls won`t begin until late Thursday and into Friday.

Temperatures will fall another 7-11 deg F between 11 pm
Wed-7am Thu. 3-6mb pressure rises in 3hr along with strong CAA
will promote brisk wind gusts between 30-40 mph through 06Z Thu
before the wind slowly decreases through the overnight.

Min temps will be 10-20 degrees lower vs. last night in the
30-40F range by daybreak Thursday with an added wind chill
factor.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
Overall confidence is continuing to increase for the first
impactful winter weather storm of the season. The latest
guidance continued to trend towards the same two areas of focus
for higher snowfall amounts Thursday evening through Friday
night. The highest confidence remains in the south west along
the Laurels where strong upslope flow could create areas of
6-8+ inches of snow. The winter storm watch for Cambria and
Somerset counties has been upgraded to a warning as a result.

The position of the overall low shifted south westward with the
most recent guidance, but snowfall totals remain uncertain in
our north eastern counties, thus the winter storm watch for
those counties has been expanded to reflect this latest trend.

Previous Discussion...

Big pattern change unfolds for late week as complex but highly
anomalous upper level closed low spawns the first winter storm
of the season.

Two key areas of concern:

1) Northeast zones adjacent to the Poconos: Elevation driven
heavy wet snow potentially setting up over a 24hr period
Thursday evening into Friday evening as robust deformation zone
pivots over northeast PA. We were keen to issue a winter storm
watch for the higher terrain zones adjacent to WFOs BGM and PHI
with multi model/ensemble trends signaling increasing
confidence in >6" near or above 1500ft.

2) Laurel Highlands: Multi-day upslope flow snow event is set
to occur from Thursday night through Saturday night impacting
the Laurel Highlands. This is our highest confidence heavy snow
risk area given a very predictable long duration NW flow
pattern. Ensemble guidance has been all over this going back
more than a week and now short range blends indicate high odds
for >6" of snow above 2000 feet. A winter storm warning has been
issued for Somerset and Cambria Counties as confidence in heavy
snowfall is high.

A general 1-3 inches is forecast over the northwest Allegheny
Mountains with some potential for local 3-6". Lower elevations
along and to the southeast of I99/I80 corridor could pick up a
slushy coating to an inch or so by the weekend, with very little
to no snow accum expected in the lower Susq Valley. Blustery
winds and heavy wet snow could result in moderate impacts (WSSI)
particularly in the higher elevations, but any accums in the
valleys would likely occur on grass and elevated surfaces.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Lingering lake effect/orographic snow over the Northern and
Western Mountains Saturday (with scattered valley rain and wet
snow showers) as one or more fast-moving and weak shortwaves
moves SE from the Glakes Region. This light precip will
dwindle by late Sunday afternoon, as subsidence inversion
heights fall and high pressure approaches from the Tennessee
Valley. Milder conditions look likely next Monday ahead of an
approaching, rather potent cold front, which could produce late
afternoon/early nighttime rain showers with the core of energy
aloft progged to move across the Upper Great Lakes region.

Brisk west winds and colder air pushing into the region for
Tuesday with scattered rain showers in the valleys and mixed
rain/snow showers over the higher terrain of the Laurels and NW
Mtns.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
06z update... A frontal band of rain showers is progressing
quickly across the Commonwealth and it should be through
central PA by 08-09z. MVFR restrictions are the most likely
scenario during this timeframe, mainly for KIPT.

A dry slot behind the front should result primarily in
unrestricted conditions through early to mid-afternoon (17-20z).
Confidence in this scenario is fairly high (70-80%) for most
central PA terminal sites. The exception to this is along the
Allegheny front at KJST, where we expect lower clouds to
redevelop by 11-14z. We have 50-60% confidence in this.

Later this afternoon and evening, conditions should deteriorate
at KIPT (light rain and snow), as well as KBFD and KJST (light
snow). KJST will likely see IFR reductions (70-80% confidence),
with KBFD also probably sinking into IFR conditions by later
this evening. If KIPT keeps a rain/snow mix, MVFR is foreseen,
but prevailing snow would mean lower visibilities and IFR.

KAOO, KUNV, KMDT, and KLNS are expected to stay unrestricted
(60-80% confident) through this evening.

Gusty W-NW surface winds will diminish for a time later this
morning, before picking up again later this afternoon and
tonight (gusts of 20-25 kt common).

Outlook...

Fri-Sat...Restrictions likely with rain and snow showers,
mainly across the mountains (KBFD and KJST). MVFR much of the
time for KUNV/KIPT/KAOO. Mainly VFR at KLNS and KMDT. Windy.

Sun-Mon...Lingering showers near KBFD and KJST.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 1 PM this afternoon to 7 AM EST
Saturday for PAZ004-005-010>012-017-018.
Winter Storm Watch from this afternoon through Friday
afternoon for PAZ006-037-041-042-058.
Wind Advisory until 1 AM EST early this morning for PAZ017>019-
024>028-033>036-056-057-059-063>066.
Winter Storm Warning from 1 PM this afternoon to 7 AM EST
Saturday for PAZ024-033.

&&

$$

SYNOPSIS...Lambert/Steinbugl
NEAR TERM...Lambert/Steinbugl/Bowen
SHORT TERM...Steinbugl/Bowen
LONG TERM...Lambert
AVIATION...Jurewicz/Lambert/Bauco

Latest Public Information Statement:

656
NOUS41 KCTP 210350
PNSCTP
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-056>059-
063>066-211550-

Public Information Statement
National Weather Service State College PA
1050 PM EST Wed Nov 20 2024

...HIGHEST WIND REPORTS (AT LEAST 30 MPH)...

Location Speed Time/Date Provider

...Pennsylvania...

...Adams County...
Gettysburg 45 MPH 0844 PM 11/20 CWOP
Cashtown 41 MPH 0845 PM 11/20 CWOP

...Bedford County...
Claysburg 42 MPH 0741 PM 11/20 CWOP
Bedford Airport 38 MPH 0655 PM 11/20 AWOS

...Blair County...
Martinsburg 39 MPH 0734 PM 11/20 AWOS
Blair Helibase 31 MPH 0716 PM 11/20 RAWS

...Cambria County...
Johnstown Airport 51 MPH 0624 PM 11/20 ASOS

...Cameron County...
Doll Hill 35 MPH 0750 PM 11/20 RAWS

...Centre County...
Bear Knob 41 MPH 0849 PM 11/20 RAWS
AccuWeather HQ 37 MPH 0845 PM 11/20 CWOP
PSU Beaver Stadium WxSTEM 34 MPH 0820 PM 11/20 MESOWEST
Rock Springs 32 MPH 0745 PM 11/20 MESOWEST
Stormstown 32 MPH 0830 PM 11/20 CWOP
State College 31 MPH 0800 PM 11/20 CWOP
PSU Arboretum WxSTEM 31 MPH 0800 PM 11/20 MESOWEST
Stormstown 30 MPH 0836 PM 11/20 CWOP

...Clearfield County...
Clearfield Airport 47 MPH 0712 PM 11/20 ASOS
Kennedy Preserve 30 MPH 0808 PM 11/20 RAWS

...Clinton County...
Lock Haven Airport 39 MPH 0909 PM 11/20 AWOS
Coffin Rock 36 MPH 0916 PM 11/20 RAWS

...Dauphin County...
Harrisburg Intl Airport 41 MPH 0944 PM 11/20 ASOS
Harrisburg 38 MPH 1013 PM 11/20 CWOP
Reach Cyber CharSch WxSTEM 33 MPH 0940 PM 11/20 MESOWEST
Hummelstown 32 MPH 1026 PM 11/20 CWOP
Paxtonia 30 MPH 1009 PM 11/20 CWOP

...Elk County...
St Marys 33 MPH 0715 PM 11/20 AWOS

...Franklin County...
Marion 37 MPH 0820 PM 11/20 CWOP
Chambersburg 33 MPH 0820 PM 11/20 CWOP
Mercersburg 32 MPH 0745 PM 11/20 DAVIS
Waynesboro 32 MPH 0821 PM 11/20 CWOP
Chambersburg 30 MPH 0811 PM 11/20 DAVIS

...Fulton County...
Forney Trail 31 MPH 0749 PM 11/20 RAWS

...Lancaster County...
Manheim 46 MPH 1015 PM 11/20 CWOP
Lancaster Airport 44 MPH 1029 PM 11/20 ASOS
NEW PROVIDENCE 38 MPH 1020 PM 11/20 CWOP
Holtwood 38 MPH 1030 PM 11/20 CWOP
Mount Joy 32 MPH 1015 PM 11/20 CWOP
MOUNT JOY 31 MPH 1025 PM 11/20 CWOP

...Lebanon County...
Muir Airfield Ft. Indiantown 44 MPH 1019 PM 11/20 AWOS
Palmyra 38 MPH 1010 PM 11/20 CWOP

...Lycoming County...
Williamsport Airport 44 MPH 0956 PM 11/20 ASOS

...McKean County...
Bradford Airport 45 MPH 0704 PM 11/20 ASOS

...Mifflin County...
Mifflin County Airport-RVL 41 MPH 0835 PM 11/20 AWOS
Chestnut Springs 32 MPH 0951 PM 11/20 RAWS

...Perry County...
Shermans Dale 32 MPH 0905 PM 11/20 CWOP
Duncannon 31 MPH 0925 PM 11/20 CWOP

...Schuylkill County...
POTTSVILLE 31 MPH 1015 PM 11/20 CWOP

...Snyder County...
Selinsgrove 36 MPH 0940 PM 11/20 ASOS

...Somerset County...
Somerset 40 MPH 0620 PM 11/20 CWOP
Somerset Airport 36 MPH 0915 PM 11/20 AWOS
Meyersdale 32 MPH 0635 PM 11/20 CWOP
Flight 93 Memorial Site 30 MPH 0716 PM 11/20 MESOWEST

...Tioga County...
Wellsboro Airport 35 MPH 0955 PM 11/20 AWOS

...Union County...
Lewisburg 32 MPH 1000 PM 11/20 CWOP

...York County...
Capitol City Airport 38 MPH 0927 PM 11/20 ASOS
York Airport 35 MPH 0923 PM 11/20 ASOS
Dover 31 MPH 0935 PM 11/20 CWOP
&&

**METADATA**
:11/20/2024,0845 PM, PA, Adams, Cashtown, , , 39.88, -77.35, PKGUST, 41, mph, CWOP, Peak Wind Gust,
:11/20/2024,0844 PM, PA, Adams, Gettysburg, , , 39.7832, -77.2687, PKGUST, 45, mph, CWOP, Peak Wind Gust,
:11/20/2024,0655 PM, PA, Bedford, Bedford Airport, , , 40.0833, -78.5167, PKGUST, 38, mph, AWOS, Peak Wind Gust,
:11/20/2024,0741 PM, PA, Bedford, Claysburg, , , 40.2599, -78.4924, PKGUST, 42, mph, CWOP, Peak Wind Gust,
:11/20/2024,0716 PM, PA, Blair, Blair Helibase, , , 40.4417, -78.4197, PKGUST, 31, mph, RAWS, Peak Wind Gust,
:11/20/2024,0734 PM, PA, Blair, Martinsburg, , , 40.2999, -78.3168, PKGUST, 39, mph, AWOS, Peak Wind Gust,
:11/20/2024,0624 PM, PA, Cambria, Johnstown Airport, , , 40.3167, -78.8333, PKGUST, 51, mph, ASOS, Peak Wind Gust,
:11/20/2024,0750 PM, PA, Cameron, Doll Hill, , , 41.6059, -78.2365, PKGUST, 35, mph, RAWS, Peak Wind Gust,
:11/20/2024,0836 PM, PA, Centre, Stormstown, , , 40.8062, -77.998, PKGUST, 30, mph, CWOP, Peak Wind Gust,
:11/20/2024,0800 PM, PA, Centre, State College, , , 40.8006, -77.8707, PKGUST, 31, mph, CWOP, Peak Wind Gust,
:11/20/2024,0800 PM, PA, Centre, PSU Arboretum WxSTEM, , , 40.8064, -77.869, PKGUST, 31, mph, MESOWEST, Peak Wind Gust,
:11/20/2024,0745 PM, PA, Centre, Rock Springs, , , 40.71, -77.952, PKGUST, 32, mph, MESOWEST, Peak Wind Gust,
:11/20/2024,0830 PM, PA, Centre, Stormstown, , , 40.7912, -78.0117, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,0820 PM, PA, Centre, PSU Beaver Stadium WxSTEM, , , 40.8121, -77.856, PKGUST, 34, mph, MESOWEST, Peak Wind Gust,
:11/20/2024,0845 PM, PA, Centre, AccuWeather HQ, , , 40.7816, -77.897, PKGUST, 37, mph, CWOP, Peak Wind Gust,
:11/20/2024,0849 PM, PA, Centre, Bear Knob, , , 40.9316, -77.9466, PKGUST, 41, mph, RAWS, Peak Wind Gust,
:11/20/2024,0808 PM, PA, Clearfield, Kennedy Preserve, , , 41.1047, -78.4917, PKGUST, 30, mph, RAWS, Peak Wind Gust,
:11/20/2024,0712 PM, PA, Clearfield, Clearfield Airport, , , 41.05, -78.4167, PKGUST, 47, mph, ASOS, Peak Wind Gust,
:11/20/2024,0916 PM, PA, Clinton, Coffin Rock, , , 41.2378, -77.7517, PKGUST, 36, mph, RAWS, Peak Wind Gust,
:11/20/2024,0909 PM, PA, Clinton, Lock Haven Airport, , , 41.136, -77.4219, PKGUST, 39, mph, AWOS, Peak Wind Gust,
:11/20/2024,1009 PM, PA, Dauphin, Paxtonia, , , 40.2953, -76.767, PKGUST, 30, mph, CWOP, Peak Wind Gust,
:11/20/2024,1026 PM, PA, Dauphin, Hummelstown, , , 40.3185, -76.6908, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,0940 PM, PA, Dauphin, Reach Cyber CharSch WxSTEM, , , 40.2709, -76.8137, PKGUST, 33, mph, MESOWEST, Peak Wind Gust,
:11/20/2024,1013 PM, PA, Dauphin, Harrisburg, , , 40.3263, -76.8988, PKGUST, 38, mph, CWOP, Peak Wind Gust,
:11/20/2024,0944 PM, PA, Dauphin, Harrisburg Intl Airport, , , 40.2, -76.7667, PKGUST, 41, mph, ASOS, Peak Wind Gust,
:11/20/2024,0715 PM, PA, Elk, St Marys, , , 41.4167, -78.5, PKGUST, 33, mph, AWOS, Peak Wind Gust,
:11/20/2024,0811 PM, PA, Franklin, Chambersburg, , , 39.86, -77.5987, PKGUST, 30, mph, DAVIS, Peak Wind Gust,
:11/20/2024,0745 PM, PA, Franklin, Mercersburg, , , 39.7401, -77.9386, PKGUST, 32, mph, DAVIS, Peak Wind Gust,
:11/20/2024,0821 PM, PA, Franklin, Waynesboro, , , 39.7603, -77.5422, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,0820 PM, PA, Franklin, Chambersburg, , , 39.9525, -77.5943, PKGUST, 33, mph, CWOP, Peak Wind Gust,
:11/20/2024,0820 PM, PA, Franklin, Marion, , , 39.8338, -77.6637, PKGUST, 37, mph, CWOP, Peak Wind Gust,
:11/20/2024,0749 PM, PA, Fulton, Forney Trail, , , 39.9934, -77.9589, PKGUST, 31, mph, RAWS, Peak Wind Gust,
:11/20/2024,1025 PM, PA, Lancaster, MOUNT JOY, , , 40.1177, -76.5377, PKGUST, 31, mph, CWOP, Peak Wind Gust,
:11/20/2024,1015 PM, PA, Lancaster, Mount Joy, , , 40.1133, -76.4993, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,1020 PM, PA, Lancaster, NEW PROVIDENCE, , , 40.0475, -76.3038, PKGUST, 38, mph, CWOP, Peak Wind Gust,
:11/20/2024,1030 PM, PA, Lancaster, Holtwood, , , 39.8878, -76.2513, PKGUST, 38, mph, CWOP, Peak Wind Gust,
:11/20/2024,1029 PM, PA, Lancaster, Lancaster Airport, , , 40.1167, -76.3, PKGUST, 44, mph, ASOS, Peak Wind Gust,
:11/20/2024,1015 PM, PA, Lancaster, Manheim, , , 40.1673, -76.4545, PKGUST, 46, mph, CWOP, Peak Wind Gust,
:11/20/2024,1010 PM, PA, Lebanon, Palmyra, , , 40.2978, -76.5755, PKGUST, 38, mph, CWOP, Peak Wind Gust,
:11/20/2024,1019 PM, PA, Lebanon, Muir Airfield Ft. Indiantown Gap, , , 40.4167, -76.5667, PKGUST, 44, mph, AWOS, Peak Wind Gust,
:11/20/2024,0956 PM, PA, Lycoming, Williamsport Airport, , , 41.25, -76.9167, PKGUST, 44, mph, ASOS, Peak Wind Gust,
:11/20/2024,0704 PM, PA, McKean, Bradford Airport, , , 41.8, -78.6333, PKGUST, 45, mph, ASOS, Peak Wind Gust,
:11/20/2024,0951 PM, PA, Mifflin, Chestnut Springs, , , 40.6914, -77.7026, PKGUST, 32, mph, RAWS, Peak Wind Gust,
:11/20/2024,0835 PM, PA, Mifflin, Mifflin County Airport-RVL, , , 40.6833, -77.6333, PKGUST, 41, mph, AWOS, Peak Wind Gust,
:11/20/2024,0925 PM, PA, Perry, Duncannon, , , 40.4745, -76.9665, PKGUST, 31, mph, CWOP, Peak Wind Gust,
:11/20/2024,0905 PM, PA, Perry, Shermans Dale, , , 40.3246, -77.1206, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,1015 PM, PA, Schuylkill, POTTSVILLE, , , 40.6995, -76.3117, PKGUST, 31, mph, CWOP, Peak Wind Gust,
:11/20/2024,0940 PM, PA, Snyder, Selinsgrove, , , 40.8167, -76.8667, PKGUST, 36, mph, ASOS, Peak Wind Gust,
:11/20/2024,0716 PM, PA, Somerset, Flight 93 Memorial Site, , , 40.062, -78.9024, PKGUST, 30, mph, MESOWEST, Peak Wind Gust,
:11/20/2024,0635 PM, PA, Somerset, Meyersdale, , , 39.8118, -79.0285, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,0915 PM, PA, Somerset, Somerset Airport, , , 40.0333, -79.0167, PKGUST, 36, mph, AWOS, Peak Wind Gust,
:11/20/2024,0620 PM, PA, Somerset, Somerset, , , 40.0738, -79.17, PKGUST, 40, mph, CWOP, Peak Wind Gust,
:11/20/2024,0955 PM, PA, Tioga, Wellsboro Airport, , , 41.7333, -77.4, PKGUST, 35, mph, AWOS, Peak Wind Gust,
:11/20/2024,1000 PM, PA, Union, Lewisburg, , , 40.9802, -76.8863, PKGUST, 32, mph, CWOP, Peak Wind Gust,
:11/20/2024,0935 PM, PA, York, Dover, , , 39.9885, -76.8456, PKGUST, 31, mph, CWOP, Peak Wind Gust,
:11/20/2024,0923 PM, PA, York, York Airport, , , 39.9167, -76.8833, PKGUST, 35, mph, ASOS, Peak Wind Gust,
:11/20/2024,0927 PM, PA, York, Capitol City Airport, , , 40.2167, -76.85, PKGUST, 38, mph, ASOS, Peak Wind Gust,

Observations are collected from a variety of sources with varying
equipment and exposures. We thank all volunteer weather observers
for their dedication. Not all data listed are considered official.

$$
NPB