Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 110, NWS State College, PA

July 29, 2009Adams County, Cumberland County, Franklin County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 29, 2009, 5:46 PM EDT for Adams County, Cumberland County, Franklin County, Pennsylvania. It was in force for 59 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: Jul 29, 2009, 5:46 PM EDT (21:46 UTC)
Expired: Jul 29, 2009, 6:45 PM EDT
In force: 59 min
Issued by: NWS State College, PA
Area: Storm-based polygon

Counties Adams County, PA, Cumberland County, PA, Franklin County, PA

The radar

The Sterling radar (KLWX), 113 km from the middle of the area, began a volume at 21:46 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.8 hours before the alert went out and 115 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: 364 J/kg
Mixed-layer CIN: -129 J/kg
Mixed-layer LCL: 1297 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 73 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

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 Jul 29, 4:00 PM EDT, 1 hour 46 minutes earlier.

Area forecast discussion, Jul 29, 4:00 PM EDT, 1 hour 46 minutes before

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Hazardous weather outlook, Jul 29, 2:59 AM EDT, 14 hours 47 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
259 AM EDT WED JUL 29 2009

PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049-050-
300700-
WARREN-MCKEAN-POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD-
NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN-
JUNIATA-SOMERSET-BEDFORD-FULTON-FRANKLIN-TIOGA-NORTHERN LYCOMING-
SULLIVAN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-
259 AM EDT WED JUL 29 2009

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...THURSDAY THROUGH TUESDAY.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

PAZ051>053-056>059-063>066-300700-
MONTOUR-NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-
CUMBERLAND-ADAMS-YORK-LANCASTER-
259 AM EDT WED JUL 29 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...TODAY AND TONIGHT.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY...ALONG WITH
THE RISK OF LOCALIZED FLOODING FROM HEAVY DOWNPOURS.

.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.

In the hours before

Special weather statement, Jul 29, 3:21 PM EDT, 2 hours 25 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
321 PM EDT WED JUL 29 2009

PAZ034>036-292000-
BEDFORD PA-FRANKLIN PA-FULTON PA-
321 PM EDT WED JUL 29 2009

...A STRONG THUNDERSTORM WILL AFFECT FULTON...SOUTH CENTRAL BEDFORD
AND SOUTHWESTERN FRANKLIN COUNTIES...

AT 319 PM EDT...A STRONG THUNDERSTORM WAS LOCATED NEAR LINEBURG...
MOVING NORTHEAST AT 30 MPH.

WIND GUSTS TO 50 MPH AND PEA-SIZED HAIL ARE POSSIBLE WITH THIS STORM.

THIS STORM WILL BE NEAR BARNES GAP AROUND 330 PM...LOCUST GROVE
AROUND 340 PM...COVE MILLS AROUND 350 PM AND NEEDMORE AROUND 400 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...THE
PENNSYLVANIA TURNPIKE BETWEEN MILE MARKERS 175 AND 181...I-70 BETWEEN
MILE MARKERS 153 AND 170.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 30...ROUTE
522.

LAT...LON 3972 7796 3972 7851 4011 7796 3974 7778
      3971 7788

EXPERIMENTAL

FORECASTER: DANGELO

Special weather statement, Jul 29, 4:01 PM EDT, 1 hour 45 minutes before

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Special weather statement, Jul 29, 4:24 PM EDT, 1 hour 22 minutes before

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Special weather statement, Jul 29, 4:37 PM EDT, 1 hour 9 minutes before

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Special weather statement, Jul 29, 5:01 PM EDT, 45 minutes before

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Special weather statement, Jul 29, 5:28 PM EDT, 18 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
Jul 29, 12:05 PM EDT	Special Weather Statement	CTP	Schuylkill	25 min
Jul 29, 2:05 PM EDT	Special Weather Statement	CTP	Northumberland	40 min
Jul 29, 2:30 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Northumberland	45 min
Jul 29, 2:44 PM EDT	Special Weather Statement	CTP	Dauphin	31 min
Jul 29, 3:03 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin	27 min
Jul 29, 3:21 PM EDT	Special Weather Statement	CTP	Fulton	39 min
Jul 29, 4:01 PM EDT	Special Weather Statement	CTP	Fulton	44 min
Jul 29, 4:24 PM EDT	Special Weather Statement	CTP	Lancaster	51 min
Jul 29, 4:37 PM EDT	Special Weather Statement	CTP	Franklin	68 min
Jul 29, 4:52 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Cumberland, Franklin	53 min
Jul 29, 5:01 PM EDT	Special Weather Statement	CTP	Franklin	14 min
Jul 29, 5:28 PM EDT	Special Weather Statement	CTP	Franklin	17 min
Jul 29, 5:38 PM EDT	Areal Flood Advisory	CTP	Franklin	3 hr
Jul 29, 7:11 PM EDT	Special Weather Statement	CTP	Schuylkill	79 min
Jul 29, 7:23 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Lebanon, Schuylkill	97 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2009 Every severe thunderstorm warning in 2009

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.