Special Weather Statement, NWS State College, PA

Area Forecast Discussion
National Weather Service State College PA
1152 AM EDT Wed Jul 21 2021

.SYNOPSIS...
A cold front is sweeping through central Pennsylvania,
producing scattered showers and thunderstorms. Behind the
front, cooler and refreshingly less humid conditions are
expected for the rest of the work week before heat and humidity
make a comeback for the weekend. Rain chances will also increase
by late Saturday and Sunday.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...
A couple of tall storms along a line of generally shallow
convection have poked up through the early morning cap to get
near-severe. The storms appear to be just ahead of the front,
but the northwest wind is developing behind the line of
convection now. SPC Meso Disco has already targeted the SErn
third/quarter of the CWA for a high poss of a svr tstm watch. So
far, no inter-office coordination on that course of action yet.
The high dewpoints to the SE of the line of convection are great
fuel. Sct SHRA and perhaps isolated TSRA are still possible
behind this first line, as some convection is popping up near
BFD, along what is perhaps the real dry air. However, that
convection is less-likely to make lightning and certainly to
become severe as it is separated by a far distance from the best
moisture.

Prev...
5h trough digging southward over the eastern GLAKS this morning,
pushing a sfc cold front into central PA. At 11z, a prefrontal
trof was extending from the Mohawk Valley to the Pocono Plateau
southwestward to the MD panhandle. Sfc cold front appears to be
extend from near KBGM to near KPBZ presently. Areas of river
valley fog will lift by 13z in most places.

Isolated -shra/tsra traversing the NC Mountains early this
morning. More widespread convection will redevelop later this
morning as aforementioned front pushes eastward and 5h trof
continues to dig over the eastern GLAKS and western PA/NY. Good
surge of low PW air arrives behind the trof later today and
tonight...something to look forward to. Thermo profiles
supportive of moderate MLCAPES by early afternoon over my
southeast, and there may be a couple buildups capable of
marginal wind gusts, with ambient environment providing 1500
J/kg MLCAPE and DCAPE of 800-900 J/kg. However, it appears the
main svr threat is east of my area. Locally heavy downpours may
accompany storms over the Middle to Lower Susq, with the
recently wet areas of the northeast needing to be watched given
low FFG values. Progressive storm motions mean this is a lower
end flood threat however.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY NIGHT/...
Cooler and drier air mass builds across the central PA tonight
and Thursday with comfortable humidity and river valley fog
confined to the deepest northern valleys. Mins will range from
near 50 over the north to the lower 60s south.

High pressure will build in from the Ohio Valley on Thursday,
bringing plenty of sunshine and mild temperatures ranging from
the mid 70s in the north to the mid 80s in southern PA.
Dewpoints in the 50s will feel quite refreshing.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A warm front will slowly approach from the west beginning on
Fri, bringing with it a slight chance of showers and storms to
the NW. The warm front will advance across the rest of PA on
Saturday, again bringing a chance for isolated showers and
storms, but very dry midlevel air will keep coverage limited and
widespread rainfall does not appear likely.

Moisture will flow back into the area on Sunday, with dewpoints
rising to 65-70F and temperatures returning to the 80-90F range.
Increased moisture and instability along with a weak disturbance
aloft will likely lead to more widespread showers/storms Sun
afternoon and evening.

Warm and humid conditions will continue into early next week
with a chance for additional rounds of showers and storms as
weak upper shortwave troughs pivot around a large ridge of high
pressure set up over the central US.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
Expect improving cigs across the Allegheny Plateau later
today, as drier air arrives on northwest flow. Model soundings
and ensemble prob charts support widespread VFR conditions by
Wed afternoon. However, can't rule out a gusty tstorm forming on
exiting cold front across central and southeast PA sometime
between 16-18Z.

Outlook...

Thu...AM valley fog possible W Mtns.

Fri...No sig wx expected.

Sat...Late day tsra impacts possible, mainly west.

Sun...AM low cigs possible W Mtns. PM tsra impacts possible.

&&

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

&&

SYNOPSIS...DeVoir/Banghoff
NEAR TERM...DeVoir/Dangelo/Colbert/Wagner
SHORT TERM...DeVoir/Colbert/Wagner
LONG TERM...Colbert/Travis
AVIATION...Fitzgerald/Gutierrez

Hazardous Weather Outlook
National Weather Service State College PA
1158 AM EDT Wed Jul 21 2021

PAZ004>006-010>012-017>019-024>028-033>035-037-041-042-045-046-
049>053-056-221600-
Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield-
Northern Centre-Southern Centre-Cambria-Blair-Huntingdon-Mifflin-
Juniata-Somerset-Bedford-Fulton-Tioga-Northern Lycoming-Sullivan-
Southern Clinton-Southern Lycoming-Union-Snyder-Montour-
Northumberland-Columbia-Perry-
1158 AM EDT Wed Jul 21 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...Thursday through Tuesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

PAZ036-057>059-063>066-221600-
Franklin-Dauphin-Schuylkill-Lebanon-Cumberland-Adams-York-Lancaster-
1158 AM EDT Wed Jul 21 2021

...SEVERE THUNDERSTORM WATCH 385 IN EFFECT UNTIL 8 PM EDT THIS
EVENING...

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.

   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Special Weather Statement
National Weather Service State College PA
1100 AM EDT Wed Jul 21 2021

PAZ026-036-056-063-211545-
Perry PA-Franklin PA-Cumberland PA-Huntingdon PA-
1100 AM EDT Wed Jul 21 2021

...A STRONG THUNDERSTORM WILL AFFECT PARTS OF PERRY...FRANKLIN...
CUMBERLAND...AND HUNTINGDON COUNTIES UNTIL 1145 AM EDT...

At 1059 AM EDT, Doppler radar indicated a strong thunderstorm near
Doylesburg, moving east at 25 mph.

Pea size hail and wind gusts of 50 to 55 mph are possible.

Locations impacted include...
Upper Strasburg, Roxbury, Willow Hill, Big Spring State Park,
Doylesburg and Shade Gap.

LAT...LON 4002 7766 4019 7791 4026 7782 4027 7773
      4027 7769 4023 7744
TIME...MOT...LOC 1459Z 288DEG 20KT 4022 7779

Travis

Special Weather Statement
National Weather Service State College PA
1140 AM EDT Wed Jul 21 2021

PAZ036-063-211615-
Franklin PA-Cumberland PA-
1140 AM EDT Wed Jul 21 2021

...STRONG THUNDERSTORMS WILL AFFECT PARTS OF FRANKLIN AND CUMBERLAND
COUNTIES UNTIL 1215 PM EDT...

At 1140 AM EDT, Doppler radar indicated strong thunderstorms along a
line extending from near Shippensburg to near Roxbury. Movement was
southeast at 20 mph.

Pea size hail and wind gusts up to 50 mph are possible.

Locations impacted include...
Shippensburg, Scotland, Upper Strasburg, Roxbury, Walnut Bottom, Pine
Grove Furnace, Orrstown and Shippensburg University.

LAT...LON 4004 7726 3997 7763 4010 7781 4015 7757
TIME...MOT...LOC 1540Z 296DEG 17KT 4011 7758 4010 7770

Banghoff

Special Weather Statement
National Weather Service State College PA
1159 AM EDT Wed Jul 21 2021

PAZ050-052-211630-
Northumberland PA-Snyder PA-
1159 AM EDT Wed Jul 21 2021

...STRONG THUNDERSTORMS WILL AFFECT PARTS OF NORTHUMBERLAND AND
SNYDER COUNTIES UNTIL 1230 PM EDT...

At 1158 AM EDT, Doppler radar indicated strong thunderstorms along a
line extending from Kratzerville to near Richfield. Movement was east
at 20 mph.

Pea size hail and wind gusts of 50 to 55 mph are possible.

Locations impacted include...
Sunbury, Selinsgrove, Fairview-Ferndale, Trevorton, Shamokin Dam,
Hummels Wharf, Middleburg, Kreamer, Port Trevorton, Richfield, Mount
Pleasant Mills, Kratzerville, Paxtonville, Rebuck, Meiserville,
Urban, Fremont, Stonington, Edgewood and Freeburg.

LAT...LON 4061 7689 4061 7691 4060 7692 4062 7694
      4065 7695 4064 7700 4066 7701 4066 7703
      4068 7704 4068 7709 4071 7716 4088 7694
      4083 7650
TIME...MOT...LOC 1558Z 288DEG 17KT 4084 7690 4072 7709

Banghoff

Special Weather Statement
National Weather Service State College PA
1206 PM EDT Wed Jul 21 2021

PAZ036-063-064-211630-
Adams PA-Franklin PA-Cumberland PA-
1206 PM EDT Wed Jul 21 2021

...A STRONG THUNDERSTORM WILL AFFECT PARTS OF ADAMS...FRANKLIN...AND
CUMBERLAND COUNTIES UNTIL 1230 PM EDT...

At 1205 PM EDT, Doppler radar indicated a strong thunderstorm over
Scotland, moving southeast at 15 mph.

Pea size hail and wind gusts of 50 to 55 mph are possible.

Locations impacted include...
Shippensburg, Fayetteville and Scotland.

LAT...LON 4000 7765 4007 7758 3997 7730 3983 7750
TIME...MOT...LOC 1605Z 312DEG 14KT 4000 7757

Banghoff

Special Weather Statement
National Weather Service State College PA
1222 PM EDT Wed Jul 21 2021

PAZ057-059-211700-
Lebanon PA-Dauphin PA-
1222 PM EDT Wed Jul 21 2021

...A STRONG THUNDERSTORM WILL AFFECT PARTS OF LEBANON AND DAUPHIN
COUNTIES UNTIL 100 PM EDT...

At 1222 PM EDT, Doppler radar indicated a strong thunderstorm over
Skyline View, moving east at 25 mph.

Pea size hail and wind gusts of 50 to 55 mph are possible.

Locations impacted include...
Lebanon, Hershey, Palmyra, Linglestown, Annville, Skyline View,
Campbelltown, Pleasant Hill, Cleona, Timber Hills, Lawn, Penn
National Race Course, Harper Tavern and Hershey Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4035 7680 4042 7676 4039 7643 4022 7649
      4021 7653 4021 7654
TIME...MOT...LOC 1622Z 281DEG 20KT 4037 7671

Banghoff

Special Weather Statement
National Weather Service State College PA
1228 PM EDT Wed Jul 21 2021

PAZ028-050-052-056>058-211700-
Perry PA-Northumberland PA-Juniata PA-Dauphin PA-Snyder PA-
Schuylkill PA-
1228 PM EDT Wed Jul 21 2021

...STRONG THUNDERSTORMS WILL AFFECT PARTS OF PERRY...
NORTHUMBERLAND...JUNIATA...DAUPHIN...SNYDER...AND SCHUYLKILL COUNTIES
UNTIL 100 PM EDT...

At 1227 PM EDT, Doppler radar indicated strong thunderstorms along a
line extending from near Rebuck to near Port Trevorton to near
Meiserville. Movement was southeast at 25 mph.

Penny size hail and wind gusts of 50 to 55 mph are possible.

Locations impacted include...
Millersburg, Trevorton, Lykens, Elizabethville, Williamstown, Tower
City, Port Trevorton, Klingerstown, Rebuck, Meiserville, Leck Kill,
Urban, Liverpool, Wiconisco, Hegins, Gratz, Dalmatia, Muir,
Berrysburg and Herndon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4056 7654 4047 7668 4047 7692 4059 7706
      4068 7710 4070 7692 4080 7684 4073 7641
TIME...MOT...LOC 1627Z 302DEG 20KT 4075 7681 4064 7688 4064 7703

Banghoff