Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 253, NWS State College, PA

August 17, 2019Potter County, Tioga County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Aug 17, 2019, 3:59 PM EDT for Potter County, Tioga County, Pennsylvania. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 17, 2019, 3:59 PM EDT (19:59 UTC)
Expired: Aug 17, 2019, 5:00 PM EDT
In force: 61 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Potter County, PA, Tioga County, PA

The radar

The State College radar (KCCX), 100 km from the middle of the area, began a volume at 20:02 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 8.0 hours before the alert went out and 160 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 39 J/kg
Mixed-layer CIN: -138 J/kg
Mixed-layer LCL: 1233 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 74 m²/s²
0-3 km storm-relative helicity: 126 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS State College, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 17, 3:13 PM EDT, 46 minutes earlier.

Area forecast discussion, Aug 17, 3:13 PM EDT, 46 minutes before

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Hazardous weather outlook, Aug 17, 4:12 AM EDT, 11 hours 47 minutes before

Hazardous Weather Outlook
National Weather Service State College PA
412 AM EDT Sat Aug 17 2019

PAZ004>006-010>012-017>019-037-041-042-045-046-049-051>053-180815-
Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield-
Northern Centre-Southern Centre-Tioga-Northern Lycoming-Sullivan-
Southern Clinton-Southern Lycoming-Union-Montour-Northumberland-
Columbia-
412 AM EDT Sat Aug 17 2019

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

Strong to severe thunderstorms with gusty winds, frequent cloud to
ground lightning and locally heavy rain are possible this afternoon
and evening.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Strong to severe thunderstorms with gusty winds, frequent cloud to
ground lightning and locally heavy rain are possible once again
Sunday afternoon and evening.

Hot and humid conditions are expected for the early to midweek
period, with heat indices topping out between 95 and 100 degrees for
Monday and Tuesday in the Central Valleys and Susquehanna River
Valley.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

PAZ024>028-033>036-050-056>059-063>066-180815-
Cambria-Blair-Huntingdon-Mifflin-Juniata-Somerset-Bedford-Fulton-
Franklin-Snyder-Perry-Dauphin-Schuylkill-Lebanon-Cumberland-Adams-
York-Lancaster-
412 AM EDT Sat Aug 17 2019

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Hot and humid conditions are expected for the early to midweek
period, with heat indices topping out between 100 and 105 degrees
throughout the Southern Valleys and Susquehanna River Valley on
Monday, and around 100 degrees both Tuesday and Wednesday afternoons.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Special weather statement, Aug 17, 1:34 PM EDT, 2 hours 25 minutes before

Special Weather Statement
National Weather Service State College PA
134 PM EDT Sat Aug 17 2019

PAZ059-171800-
Lebanon PA-
134 PM EDT Sat Aug 17 2019

...A STRONG THUNDERSTORM WILL AFFECT PARTS OF LEBANON COUNTY UNTIL
200 PM EDT...

At 133 PM EDT, Doppler radar indicated a strong thunderstorm over
Newmanstown, moving northeast at 15 mph.

Wind gusts up to 40 mph and pea size hail are possible.

Locations impacted include...
Lebanon, Myerstown, Sand Hill, Newmanstown, Avon, Richland,
Schaefferstown, Kleinfeltersville, Jonestown and Avon Heights.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Minor flooding may develop. Do not drive into water covering the
roadway.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4027 7626 4040 7650 4046 7637 4036 7623
      4036 7620 4032 7615
TIME...MOT...LOC 1733Z 222DEG 14KT 4032 7620

Banghoff

Special weather statement, Aug 17, 1:37 PM EDT, 2 hours 22 minutes before

Special Weather Statement
National Weather Service State College PA
137 PM EDT Sat Aug 17 2019

PAZ053-058-171830-
Columbia PA-Schuylkill PA-
137 PM EDT Sat Aug 17 2019

...A STRONG THUNDERSTORM WILL AFFECT PARTS OF SCHUYLKILL AND COLUMBIA
COUNTIES UNTIL 230 PM EDT...

At 136 PM EDT, Doppler radar indicated a strong thunderstorm over
Wilburton Number Two, moving east at 10 mph.

Wind gusts 40 to 50 mph and pea size hail are possible.

Locations impacted include...
Shenandoah, Mahanoy City, Frackville, Ashland, Girardville, Oneida,
Altamont, Englewood, Aristes, Fountain Springs, Numidia, Sheppton,
Brandonville, Wilburton Number One, Locustdale, Wilburton Number Two,
Locust Lake State Park, New Boston-Morea, Shenandoah Heights and
Ringtown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4074 7610 4077 7640 4078 7638 4083 7640
      4084 7641 4088 7641 4093 7614 4093 7611
      4092 7611
TIME...MOT...LOC 1736Z 267DEG 11KT 4083 7635

Banghoff

Special weather statement, Aug 17, 1:42 PM EDT, 2 hours 17 minutes before

Special Weather Statement
National Weather Service State College PA
142 PM EDT Sat Aug 17 2019

PAZ004-171845-
Warren PA-
142 PM EDT Sat Aug 17 2019

...A STRONG THUNDERSTORM WILL AFFECT PARTS OF WARREN COUNTY UNTIL 245
PM EDT...

At 141 PM EDT, Doppler radar indicated a strong thunderstorm near
Columbus, moving east at 30 mph.

Wind gusts 40 to 50 mph and pea size hail are possible.

Locations impacted include...
Warren, Columbus, Youngsville, Russell, Spring Creek, Lottsville,
Warren South, Garland, Chapman State Park, Sugar Grove, Starbrick and
Bear Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4200 7906 4171 7914 4181 7961 4199 7961
      4200 7960
TIME...MOT...LOC 1741Z 276DEG 25KT 4189 7968

Banghoff

Special weather statement, Aug 17, 2:42 PM EDT, 1 hour 17 minutes before

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Local storm report, Aug 17, 3:22 PM EDT, 37 minutes before

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Local storm report, Aug 17, 3:48 PM EDT, 11 minutes before

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The office that day

Everything else NWS State College, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 17, 11:38 AM EDT	Special Weather Statement	CTP	Lancaster, York	52 min
Aug 17, 12:30 PM EDT	Special Weather Statement	CTP	Lancaster	45 min
Aug 17, 1:11 PM EDT	Special Weather Statement	CTP	Lancaster	34 min
Aug 17, 1:34 PM EDT	Special Weather Statement	CTP	Lebanon	26 min
Aug 17, 1:37 PM EDT	Special Weather Statement	CTP	Schuylkill	53 min
Aug 17, 1:42 PM EDT	Special Weather Statement	CTP	Warren	63 min
Aug 17, 2:42 PM EDT	Special Weather Statement	CTP	Warren	63 min
Aug 17, 2:47 PM EDT	Severe Thunderstorm Warning	CTP	Warren	43 min
Aug 17, 3:04 PM EDT	Severe Thunderstorm Warning	CTP	McKean	56 min
Aug 17, 4:05 PM EDT	Severe Thunderstorm Warning	CTP	McKean	22 min
Aug 17, 4:57 PM EDT	Special Weather Statement	CTP	Tioga	33 min
Aug 17, 5:37 PM EDT	Severe Thunderstorm Warning	CTP	Tioga	27 min
Aug 17, 5:46 PM EDT	Severe Thunderstorm Warning	CTP	Clearfield	74 min
Aug 17, 6:49 PM EDT	Special Weather Statement	CTP	Sullivan	26 min
Aug 17, 7:22 PM EDT	Special Weather Statement	CTP	Centre	23 min
Aug 17, 7:25 PM EDT	Special Weather Statement	CTP	Sullivan	35 min
Aug 17, 7:45 PM EDT	Special Weather Statement	CTP	Mifflin	30 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019 Every severe thunderstorm warning in 2019

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.