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Latest PA Weather Summary:

968
AWUS81 KCTP 211008
RWSCTP
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-
049>053-056>059-063>066-220015-

Regional Weather Summary
National Weather Service State College PA
508 AM EST Sat Dec 21 2024

A cold and gusty northwest flow will gather moisture from the
Great Lakes, resulting in a good deal of cloudiness across
Pennsylvania today with scattered snow showers over the northern
and western tier of the commonwealth. Highs today will range from
around 20 degrees over the northern mountains, to the low 30s
across the southeast piedmont.

High pressure will build in from the west tonight and Sunday,
providing Pennsylvania with fair and cold weather, along with
diminishing wind. Any lingering snow showers over Western
Pennsylvania should taper off tonight and skies should be mostly
sunny on Sunday.

Lows tonight will range from the single digits across the northern
mountains, to the teens over the southern tier of the state. Highs
Sunday should range from the upper teens over the northern
mountains, to the 20s elsewhere.

$$

Latest Forecaster's Discussion:

623
FXUS61 KCTP 211116
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
616 AM EST Sat Dec 21 2024

.SYNOPSIS...
* Scattered lake effect & upslope snow showers linger into
Saturday as gusty northwest winds build in
* Coldest airmass of the season so far brings single digit low
temperatures by Monday morning
* Christmas Eve system with mixed precip impacts travel while
temperatures continue to moderate through the end of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Water vapor loop at 11Z shows a sharp upper level trough pushing
through Central PA. Strong forcing ahead of this feature will
support scattered snow showers across the South-Central Mtns
through around 13Z. Large scale subsidence behind this feature
should end the risk of snow showers east of the Alleghenies by
mid morning. Lingering lake-enhanced orographic snow showers
will continue to affect the Laurel Highlands and the N Mtns
today. However, falling inversion heights behind the exiting
upper level trough will result in only minimal additional
accumulations, with perhaps up to an inch along the Laurel Ridge
or in the snowbelt of Northwest Warren County.

A deepening surface low lifting into the Canadian Maritimes
will result in a fairly tight pressure gradient over PA today,
producing gusty northwest winds. BUFKIT soundings suggest 20 to
30kt gusts are likely, mainly during the afternoon hours. Early
morning satellite imagery is showing developing breaks in the
stratocu, especially east of the Alleghenies. However, diurnal
heating and cold temps aloft should result in clouds filling in
by midday, with mostly cloudy skies even across the Susq Valley
at times.

Cloud cover and low level cold advection should result in
little warming today. Mixing down model 850mb temps of
-14C to -16C yields expected highs from only around 20F across
the N Mtns, to the low 30s in the Lower Susq Valley. The gusty
northwest wind should result in midday wind chills in the single
digits over the N Mtns and teens most other locations.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
Dwindling lake effect snow showers/flurries over the NW
Mtns/Laurel Highlands are expected tonight, as high pressure
approaches from the Grt Lks. The cold will be the main story,
with min temps in the single digits over the N Mtns to mid teens
in the southeast counties. Although winds are expected to
diminish tonight, radiational cooling will not be ideal due to
a lingering breeze over the eastern counties and lingering
lake effect stratocu over the Laurels and NW Mtns.

Mostly sunny and cold weather with light winds are expected
Sunday, as high pressure builds over the state. GEFS 2m temp
anomalies are 10-15 degrees below average, translating to highs
ranging from the mid to upper teens over the N Mtns, to the mid
and upper 20s in the valleys of Southern PA. Even though highs
will be several degrees below those of Saturday, the
combination of sunshine and lighter winds may actually make it
slightly more pleasant to be outside on Sunday afternoon.

With high pressure overnight Sunday night, ideal conditions for
radiational cooling will undoubtedly lead to the coldest low
temperatures yet this winter by Monday morning. Lows will
generally be in the single digits with below zero temperatures
favored in northeast PA.

Return southerly flow behind the departing high will help
temperatures rebound some on Monday as high clouds stream in
ahead of the next system. Current medium range guidance
indicates most of the day will be dry, but precipitation could
arrive in northwest PA by Monday evening.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A fairly fast moving, northern stream shortwave will cross PA
late Monday into Tuesday and bring some light snow to the area.
Best chance for -SN and a light accum of a coating to 2 inches
will be across the Northern Mtns of the state. Some travel
disruptions are possible for I-80, but significant accumulations
appear unlikely at this point. GFS and its ensembles are
further north with the track of the mid and upper level trough,
but QPF along the trailing cold front leads to a similar outcome
to the EC with respect to Snow Probs/Amounts.

More of a blocky/split flow pattern develops across the entire
CONUS as we head through Christmas Eve and Christmas Day. Models
indicate a general dry and chilly Christmas Day with max temps
ranging from the low to mid 30s NE to the low 40s in the Metro
Areas of southern PA. With similar temperatures on Tuesday
across the region, prospects of a white Christmas are looking
rather bleak for all but the northern tier of PA.

Later in the week, predictability drops off quite a bit with
fairly weak forcing and a very wiggly 500mb pattern. With high
pressure to the northeast, it appears precipitation chances will
be higher in southern PA. Relatively low moisture/PWATs indicate
that QPF should be low, but persistent easterly flow could
create some risk for a wintry mix and some freezing rain with
any organized precipitation. Have kept precip as all rain or
snow at this point, but will continue to monitor the threat.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
A few snow showers are progressing across the western airfields
this morning causing MVFR to IFR visibilities and ceilings due
to snowfall. These upslope and lake effect streamer bands of
snow should gradually drift further west as flow over lake Erie
becomes more northerly. However low ceilings are likely to
persist over BFD until tonight, and upslope snow will keep JST
in MVFR conditions most of the day. A few hours of improved
conditions should occur at the western sites, but low clouds
will likely quickly build back in during the overnight period
tonight.

VFR conditions will be likely across the Central Ridge and
Valley Region after 12Z TAF package. Surface winds will be gusty
out of the north today as well, with all sites expecting to see
wind gusts near 25kts until near 06Z tonight.

Outlook...

Sat...Lingering SHSN NW/SW PA; Gusty winds ~25-30kts across the
higher elevations during the late AM/PM hours.

Sun...SHSN Far NW PA; otherwise, no sig wx.

Mon...No sig wx.

Tue...Snow enters W PA AM, overspreads area by afternoon.

Wed...Residual showers early. Becoming VFR.

&&

.CLIMATE...
Astronomical winter (solstice) begins on Saturday, December 21st
at 4:19 a.m. EST.

&&

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

&&

$$

SYNOPSIS...Banghoff
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald
LONG TERM...Lambert/Banghoff/NPB
AVIATION...Bowen
CLIMATE...Steinbugl

Latest Public Information Statement:

418
NOUS41 KCTP 210303
PNSCTP
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-056>059-
063>066-211503-

Public Information Statement
National Weather Service State College PA
1003 PM EST Fri Dec 20 2024

...SNOWFALL REPORTS...

Location Amount Time/Date Provider

...Pennsylvania...

...Centre County...
Zion 1.5 in 0300 PM 12/20 NWS Employee
3 S Unionville 1.0 in 1212 PM 12/20 Public

...Clinton County...
1 SW Mill Hall 3.0 in 0912 PM 12/20 Public

...Columbia County...
Bloomsburg 2.0 in 0535 PM 12/20 Public
3 WNW Bloomsburg 2.0 in 0730 PM 12/20

...Dauphin County...
2 ENE Elizabethville 2.2 in 0901 PM 12/20 Trained Spotter
Elizabethville 1.0 in 0330 PM 12/20 Public

...Lancaster County...
Maytown 2.0 in 0625 PM 12/20
Elizabethtown 2.0 in 0700 PM 12/20 Trained Spotter
1 E Lancaster 2.0 in 0837 PM 12/20
Akron 2.0 in 0845 PM 12/20 Trained Spotter
Ephrata 1.7 in 0830 PM 12/20 Trained Spotter
1 WNW Lancaster 1.3 in 0620 PM 12/20 NWS Employee
2 SW Manheim 1.1 in 0400 PM 12/20 Public
Bainbridge 1.0 in 0830 PM 12/20 Public

...Lebanon County...
Lebanon 2.0 in 0645 PM 12/20 Trained Spotter
1 WSW Lebanon 1.0 in 0250 PM 12/20 Trained Spotter
1 NE Palmyra 1.0 in 0320 PM 12/20 Public
1 S Palmyra 1.0 in 0328 PM 12/20 Public

...Northumberland County...
Montandon 3.5 in 0547 PM 12/20 Public
Northumberland 2.5 in 0337 PM 12/20 Public
Watsontown 2.0 in 0144 PM 12/20 Public

...Perry County...
Liverpool 1.3 in 0454 PM 12/20 Public

...Potter County...
Coudersport 2.0 in 0916 PM 12/20 Trained Spotter

...Schuylkill County...
3 NE Tremont 2.0 in 0922 PM 12/20
2 W Hometown 1.2 in 0630 PM 12/20 Public
3 WSW Hometown 1.1 in 0615 PM 12/20 Public

...Snyder County...
2 SE Beavertown 1.9 in 0451 PM 12/20 Public

...Union County...
1 WNW Linntown 2.5 in 0440 PM 12/20 Public

...York County...
Stewartstown 1.2 in 0440 PM 12/20 Public
1 E Seven Valleys 0.8 in 0304 PM 12/20 Trained Spotter
Hanover 0.4 in 0234 PM 12/20
&&

**METADATA**
:12/20/2024,1212 PM, PA, Centre, 3 S Unionville, , , 40.85625, -77.865, SNOW_24, 1, Inch, Public, 24 hour snowfall,
:12/20/2024,0300 PM, PA, Centre, Zion, , , 40.9187, -77.6709, SNOW_24, 1.5, Inch, NWS Employee, 24 hour snowfall,
:12/20/2024,0912 PM, PA, Clinton, 1 SW Mill Hall, , , 41.0952, -77.4989, SNOW_24, 3.0, Inch, Public, 24 hour snowfall,
:12/20/2024,0535 PM, PA, Columbia, Bloomsburg, , , 41.0023, -76.4569, SNOW, 2, Inch, Public, Storm total snowfall,
:12/20/2024,0730 PM, PA, Columbia, 3 WNW Bloomsburg, , , 41.023, -76.5087, SNOW, 2.0, Inch, null, Storm total snowfall,
:12/20/2024,0330 PM, PA, Dauphin, Elizabethville, , , 40.5475, -76.816, SNOW, 1, Inch, Public, Storm total snowfall,
:12/20/2024,0901 PM, PA, Dauphin, 2 ENE Elizabethville, , , 40.5639798, -76.7770902, SNOW_24, 2.2, Inch, Trained Spotter, 24 hour snowfall,
:12/20/2024,0830 PM, PA, Lancaster, Bainbridge, , , 40.09, -76.67, SNOW_24, 1.0, Inch, Public, 24 hour snowfall,
:12/20/2024,0400 PM, PA, Lancaster, 2 SW Manheim, , , 40.1441, -76.4201, SNOW_24, 1.1, Inch, Public, 24 hour snowfall,
:12/20/2024,0620 PM, PA, Lancaster, 1 WNW Lancaster, , , 40.0437, -76.3115, SNOW_24, 1.3, Inch, NWS Employee, 24 hour snowfall,
:12/20/2024,0830 PM, PA, Lancaster, Ephrata, , , 40.1781, -76.1764, SNOW_24, 1.7, Inch, Trained Spotter, 24 hour snowfall,
:12/20/2024,0625 PM, PA, Lancaster, Maytown, , , 40.0755, -76.5827, SNOW, 2.0, Inch, null, Storm total snowfall,
:12/20/2024,0700 PM, PA, Lancaster, Elizabethtown, , , 40.1536, -76.5986, SNOW, 2, Inch, Trained Spotter, Storm total snowfall,
:12/20/2024,0837 PM, PA, Lancaster, 1 E Lancaster, , , 40.0422, -76.2817, SNOW, 2.0, Inch, null, Storm total snowfall,
:12/20/2024,0845 PM, PA, Lancaster, Akron, , , 40.1601, -76.2001, SNOW_24, 2.0, Inch, Trained Spotter, 24 hour snowfall,
:12/20/2024,0250 PM, PA, Lebanon, 1 WSW Lebanon, , , 40.330266, -76.446348, SNOW_24, 1, Inch, Trained Spotter, 24 hour snowfall,
:12/20/2024,0320 PM, PA, Lebanon, 1 NE Palmyra, , , 40.319730421598, -76.581581078961, SNOW, 1, Inch, Public, Storm total snowfall,
:12/20/2024,0328 PM, PA, Lebanon, 1 S Palmyra, , , 40.299301, -76.593269, SNOW_24, 1, Inch, Public, 24 hour snowfall,
:12/20/2024,0645 PM, PA, Lebanon, Lebanon, , , 40.3413, -76.4233, SNOW, 2, Inch, Trained Spotter, Storm total snowfall,
:12/20/2024,0144 PM, PA, Northumberland, Watsontown, , , 41.0847, -76.8646, SNOW_24, 2, Inch, Public, 24 hour snowfall,
:12/20/2024,0337 PM, PA, Northumberland, Northumberland, , , 40.8971, -76.7937, SNOW, 2.5, Inch, Public, Storm total snowfall,
:12/20/2024,0547 PM, PA, Northumberland, Montandon, , , 40.96, -76.86, SNOW_24, 3.5, Inch, Public, 24 hour snowfall,
:12/20/2024,0454 PM, PA, Perry, Liverpool, , , 40.5724, -76.9928, SNOW, 1.3, Inch, Public, Storm total snowfall,
:12/20/2024,0916 PM, PA, Potter, Coudersport, , , 41.7742, -78.0143, SNOW_24, 2.0, Inch, Trained Spotter, 24 hour snowfall,
:12/20/2024,0615 PM, PA, Schuylkill, 3 WSW Hometown, , , 40.8122, -76.0441, SNOW_24, 1.1, Inch, Public, 24 hour snowfall,
:12/20/2024,0630 PM, PA, Schuylkill, 2 W Hometown, , , 40.8171, -76.0268, SNOW_24, 1.2, Inch, Public, 24 hour snowfall,
:12/20/2024,0922 PM, PA, Schuylkill, 3 NE Tremont, , , 40.655, -76.3546, SNOW, 2.0, Inch, null, Storm total snowfall,
:12/20/2024,0451 PM, PA, Snyder, 2 SE Beavertown, , , 40.732134459247, -77.142696510544, SNOW, 1.9, Inch, Public, Storm total snowfall,
:12/20/2024,0440 PM, PA, Union, 1 WNW Linntown, , , 40.964096431168, -76.919241962281, SNOW, 2.5, Inch, Public, Storm total snowfall,
:12/20/2024,0234 PM, PA, York, Hanover, , , 39.8066, -76.9786, SNOW, 0.4, Inch, null, Storm total snowfall,
:12/20/2024,0304 PM, PA, York, 1 E Seven Valleys, , , 39.85, -76.74, SNOW_24, 0.75, Inch, Trained Spotter, 24 hour snowfall,
:12/20/2024,0440 PM, PA, York, Stewartstown, , , 39.7524, -76.593, SNOW, 1.2, Inch, Public, Storm total snowfall,

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.

$$