Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 5, NWS State College, PA

March 9, 2002Lancaster County, York County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Mar 9, 2002, 11:17 PM EST for Lancaster County, York County, Pennsylvania. It was in force for 73 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Mar 9, 2002, 11:17 PM EST (04:17 UTC)
Expired
Mar 10, 2002, 12:30 AM EST
In force
73 min
Issued by
NWS State College, PA
Area
Whole counties

Counties Lancaster County, PA, York County, PA

The radar

The Sterling radar (KLWX), 141 km from the middle of the area, began a volume at 04:19 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.

What was reported inside it

TimeReportWhereRemark
Mar 9, 11:35 PM ESTThunderstorm Wind 50 EYork, PATrees and wires were reported down in York.
Mar 10, 12:10 AM ESTThunderstorm Wind 50 EEphrata, PATrees were reported down in Ephrata.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Mar 9, 8:30 PM ESTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 4.3 hours before the alert went out and 139 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-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2002-03-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 445 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2002-03-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 375 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
445 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
657 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
375 m²/s²
0-3 km storm-relative helicity
418 m²/s²
Significant tornado parameter
0.6
Supercell composite
4.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS51 KCTP 100417
SVRCTP
PAC071-133-100530-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1114 PM EST SAT MAR 9 2002

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  LANCASTER COUNTY IN PENNSYLVANIA
  YORK COUNTY IN PENNSYLVANIA

* UNTIL 1230 AM EST.

* AT 1114 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS FROM 8 MILES NORTH OF VALLEY GREEN TO
  7 MILES SOUTHWEST OF PENNVILLE...MOVING EAST AT 35 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  SPRING GROVE AT 1120 PM.
  YORK AND MANCHESTER AT 1125 PM.
  ELIZABETHTOWN AND CODORUS AT 1130 PM.
  STONYBROOK AND SPRY AT 1135 PM.
  SHREWSBURY AND RED LION AT 1140 PM.
  WRIGHTSVILLE AND WINDSOR AT 1145 PM.
  LANCASTER AT 1210 AM.

THESE STORMS HAVE A HISTORY OF PRODUCING WIND GUSTS TO 60 MPH. TAKE 
SHELTER IMMEDIATELY.

$$

&

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 9, 10:33 PM ESTSevere Thunderstorm WarningCTPColumbia, Montour, Northumberland, Snyder, Union42 min
Mar 9, 10:44 PM ESTSevere Thunderstorm WarningCTPLycoming, Sullivan31 min
Mar 9, 10:45 PM ESTSevere Thunderstorm WarningCTPDauphin, Lebanon, Schuylkill60 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2002Every severe thunderstorm warning in 2002

Sources

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