Special Weather Statement, NWS State College, PA

Area Forecast Discussion
National Weather Service State College PA
615 PM EST Sun Nov 28 2021

.SYNOPSIS...
Snow showers will fall over much of Central PA tonight as a
clipper system moves overhead.

Lingering snow showers will continue through Monday morning then
begin to lessen and fade as the day goes on. Mostly cloudy
skies will become partly sunny later Monday.

Another system approaches Tuesday with light snow expected
again.

&&

.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
Bands of snow on radar at 23Z Sunday are moving east across
Central PA. The snow begins near the leading edge of the
coldest air aloft where temps fall to -12C or lower. Some 1/2SM
visibilities are being reported with heavier bands, which may
prove problematic for evening travelers. However, most southern
areas remain above freezing at this time, so accumulations
should remain minimal until the temps drop more.

High res guidance has areas north and west of the Allegheny
Front picking up between 1 and 3 inches across the Alleghenies with the
Central Ridge and Valley region receiving a coating to one inch
by morning. The NW snowbelt will take the snow prize with 4-7
inches of snow accum over a 24 hour period near and to the NW of
a line from Bradford to Warren. A few locally higher totals are
possible.

For the Central Ridge and Valley region. A coating to one inch
will fall, mainly early tonight. However, the transition to
several narrow snowbands with a veering LLVL profile to the WNW
will blanket some locations with another quick 1/2 inch of snow.

A cold front and a few pockets of trailing very cold mid-level
air with temps dropping to below -20C will push SE across the
region late today and tonight, helping to greatly increase low-
mid level lapse rates and the threat for some brief periods of
moderate to heavy snow showers as the favorable thermal ribbon
for dendritic snow growth descends into the mid and upper
portion of the deepening cloud layer.

A Winter Weather Advisory for LES remains in effect through
early Monday morning across Warren and Mckean Counties. The
stratocu deck does shallow a bit during the day Monday, but the
base of the subsidence inversion is still AOA 7 kft across the
NW counties of the CWA with the DGZ still residing in the upper
portion of the cloud layer. So, expect to see snow showers and
areas of LES likely continuing. Will consider extending the
ending time of the Advisory into Monday afternoon for Warren and
McKean Counties.

&&

.SHORT TERM /MIDNIGHT TONIGHT THROUGH MONDAY NIGHT/...
The passage of the trough axis and onset of strong NVA will
help to diminish the intensity and longevity of the bands of LES
early Monday morning.

Early Monday, the flow is progged to veer more into the NNW just
ahead of some shortwave ridging aloft across the Glakes. In
addition, there will be increased directional shear, and also a
lowering inversion height type of environment. For the most
part, this should act to weaken lingering lake effect bands.
Expect lessening snow showers through the day Monday, with most
of the activity, if any, confined to the NW Mountains and
passably across the Laurel Highlands (if a snowband sets up
like models are hinting).

During the day Monday, the lake effect machine should further
break down over time, as heights rise aloft, and warm advection
begins to kick in above the boundary layer. However, dont expect
the snow showers to cut off completely, as that rarely occurs
downwind of the Lake Erie prior to the passage of the 850 mb
ridge axis, especially since the favorable DGZ will still
reside in the upper portion of the shallower stratocu deck.

For much of central PA, early clouds should give way to
increasing sunshine over time with flurries and a few brief snow
showers still possible.

Highs Monday afternoon should range from the lower 30s in the
northern mountains, to the lower 40s in the Lower Susquehanna
Valley. Besides the NW snowbelt, expect Monday to be dry.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Persistent upper-level troughing and WNW flow will continue
into the first half of next week.

Another clipper system will bring snow showers to Northern PA
Mon night and Tue. QPF amounts are light and the best moisture
will be outside our forecast area. A coating to 2 inches of
snow is expected in NW PA with lesser amounts elsewhere.

Temperatures will rise into the latter part of the week, with
highs on Thu expected to be in the 40s and 50s. Another clipper
system passing to the north later Thu will bring a chance of
mainly rain showers to the area, with possible snow showers behind
the front Thu night and Fri as the low moves out to the north
and east. Daytime temps in the post frontal airmass will be back
in the 30s and 40s Fri and through the weekend.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
Widespread shallow and non precipitating MVFR Stratocu across
the Central and SE zones and IFR to LIFR over the Northern and
Western Mtns will change little through tonight, though Vsbys
will greatly decrease at times as cold air aloft sweeps down
from the Great Lakes and helps to deepen/cool the cloud layer
and create an increasing frequency of snow showers.

Moderately gusty westerly winds will develop across the Central
Mtns airfields and Susq Valley TAF sites, while KJST and points
north along the spine of the Alleghenies will see Westerly
gusts of 25 to 30 KTS.

Outlook...

Mon-Tue...Restrictions possible N/W in snow showers. Breezy.

Wed...Becoming VFR areawide.

Wed night-Thu...Rain showers developing.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 7 AM EST Monday for PAZ004-005.

&&

SYNOPSIS...Wagner
NEAR TERM...Lambert/Wagner
SHORT TERM...Lambert/Wagner
LONG TERM...Colbert/Wagner
AVIATION...Lambert/Evanego/Travis

Hazardous Weather Outlook
National Weather Service State College PA
1113 AM EST Sun Nov 28 2021

PAZ012-017>019-025>028-034>037-041-042-045-046-049>053-056>059-
063>066-291615-
Northern Clinton-Clearfield-Northern Centre-Southern Centre-Blair-
Huntingdon-Mifflin-Juniata-Bedford-Fulton-Franklin-Tioga-
Northern Lycoming-Sullivan-Southern Clinton-Southern Lycoming-Union-
Snyder-Montour-Northumberland-Columbia-Perry-Dauphin-Schuylkill-
Lebanon-Cumberland-Adams-York-Lancaster-
1113 AM EST Sun Nov 28 2021

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...This afternoon and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

PAZ006-010-011-024-033-291615-
Potter-Elk-Cameron-Cambria-Somerset-
1113 AM EST Sun Nov 28 2021

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...This afternoon and tonight.

Snow accumulations will be generally an inch or two, but could be up
to 3 inches, mainly on the ridge tops and west-facing slopes late
today and tonight.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report significant hazardous weather.

PAZ004-005-291615-
Warren-McKean-
1113 AM EST Sun Nov 28 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 7 AM EST MONDAY...

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to
weather.gov/StateCollege on the internet for more
information about the following hazards.

   Winter Weather Advisory.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Please listen to NOAA Weather Radio or go to
weather.gov/StateCollege on the internet for more
information about the following hazards.

   Winter Weather Advisory.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report significant hazardous weather.

Special Weather Statement
National Weather Service State College PA
607 PM EST Sun Nov 28 2021

PAZ017>019-024>026-033-034-282345-
Bedford PA-Northern Centre PA-Somerset PA-Clearfield PA-Blair PA-
Cambria PA-Huntingdon PA-Southern Centre PA-
607 PM EST Sun Nov 28 2021

...A BAND OF SNOW SHOWERS WILL AFFECT PARTS OF BEDFORD...NORTHERN
CENTRE... SOMERSET...CLEARFIELD...BLAIR...CAMBRIA...HUNTINGDON...AND
SOUTHERN CENTRE COUNTIES...

HAZARDS...Snow showers which can rapidly reduce visibility to less
than one mile.

LOCATION AND MOVEMENT...At 604 PM EST, a band of snow showers was
along a line extending from near Moshannon to near Houtzdale to near
Derry and moving east at 45 MPH.

LOCATIONS IMPACTED INCLUDE...
Altoona, State College, Johnstown, Bellefonte, Hollidaysburg, Tyrone,
Westmont, Windber, Ebensburg, Belmont, Nanty-Glo, Portage, Park
Forest Village, Northern Cambria, Boalsburg, Pleasant Gap,
Philipsburg, Woodland, Geistown and Stormstown.

SAFETY INFO...
Use extra caution if you must travel into or through this squall.
Rapid changes in visibility and potentially slick roads may lead to
accidents.

Conditions can deteriorate rapidly in winter weather situations. Be
prepared for snow or ice covered roads. Slow down and allow extra
time to reach your destination.

&&

LAT...LON 4036 7900 4051 7891 4072 7880 4081 7880
      4104 7828 4105 7758 4097 7752 4019 7867
      4018 7912 4020 7913
TIME...MOT...LOC 2304Z 263DEG 37KT 4099 7812 4080 7851 4036 7922 4031
7946

Evanego

Special Weather Statement
National Weather Service State College PA
649 PM EST Sun Nov 28 2021

PAZ017>019-024>027-033-034-045-049-290030-
Bedford PA-Northern Centre PA-Southern Clinton PA-Union PA-
Somerset PA-Clearfield PA-Blair PA-Cambria PA-Huntingdon PA-
Mifflin PA-Southern Centre PA-
649 PM EST Sun Nov 28 2021

...BAND OF MODERATE SNOW...

HAZARDS...A band of moderate snow which can rapidly reduce
visibility to less than one mile.

LOCATION AND MOVEMENT...At 648 PM EST, a band of moderate snow was
along a line extending from Lamar to Franklinville to near Boswell
and moving east at 30 MPH.

LOCATIONS IMPACTED INCLUDE...
Altoona, State College, Johnstown, Huntingdon, Bellefonte,
Hollidaysburg, Tyrone, Westmont, Windber, Ebensburg, Belmont,
Nanty-Glo, Portage, Seven Mountains, Carroll, Woodward, Boalsburg,
Pleasant Gap, Philipsburg and Roaring Spring.

SAFETY INFO...
Use extra caution if you must travel into or through this band of
heavy snow. Rapid changes in visibility and potentially slick roads
may lead to accidents.

Conditions can deteriorate rapidly in winter weather situations. Be
prepared for snow or ice covered roads. Slow down and allow extra
time to reach your destination.

&&

LAT...LON 4012 7917 4036 7900 4052 7890 4106 7806
      4107 7714 4095 7720 4066 7762 4003 7869
      4011 7922
TIME...MOT...LOC 2348Z 276DEG 26KT 4101 7756 4067 7810 4017 7910

Evanego