Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 363

May 31, 20025 states

The Storm Prediction Center issued this severe thunderstorm watch at May 31, 2002, 5:15 PM EDT for 5 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 31, 2002, 5:15 PM EDT (21:15 UTC)
Expired
May 31, 2002, 11:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
All 63 counties

New Castle County, DE, Allegany County, MD, Baltimore County, MD, Carroll County, MD, Cecil County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Washington County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Essex County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Salem County, NJ, Somerset County, NJ, Union County, NJ, Warren County, NJ, Adams County, PA, Bedford County, PA, Berks County, PA, Blair County, PA, Bucks County, PA, Cambria County, PA, Carbon County, PA, Centre County, PA, Chester County, PA, Clearfield County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Mifflin County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Philadelphia County, PA, Schuylkill County, PA, Snyder County, PA, Union County, PA, York County, PA, Berkeley County, WV, Hampshire County, WV, Jefferson County, WV, Morgan County, WV

The radar

The State College radar (KCCX), 114 km from the middle of the area, began a volume at 21:18 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.

Warnings issued inside it

17 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 31, 5:28 PM EDTSevere Thunderstorm WarningCTPCentre, Clearfield62 min
May 31, 5:30 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia45 min
May 31, 5:40 PM EDTSevere Thunderstorm WarningCTPBlair, Cambria, Huntingdon95 min
May 31, 5:43 PM EDTSevere Thunderstorm WarningPHISussex, Warren47 min
May 31, 6:00 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Monmouth45 min
May 31, 6:21 PM EDTSevere Thunderstorm WarningCTPJuniata, Mifflin39 min
May 31, 6:25 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex50 min
May 31, 6:59 PM EDTSevere Thunderstorm WarningCTPCumberland, Perry46 min
May 31, 7:18 PM EDTSevere Thunderstorm WarningCTPBlair, Huntingdon27 min
May 31, 7:30 PM EDTSevere Thunderstorm WarningPHIWarren45 min
May 31, 8:01 PM EDTSevere Thunderstorm WarningPHIMorris44 min
May 31, 8:30 PM EDTSevere Thunderstorm WarningPHIHunterdon, Somerset45 min
May 31, 8:48 PM EDTSevere Thunderstorm WarningPHIBucks57 min
May 31, 8:58 PM EDTTornado WarningPHISomerset32 min
May 31, 9:06 PM EDTSevere Thunderstorm WarningPHIMercer, Middlesex54 min
May 31, 9:23 PM EDTSevere Thunderstorm WarningPHIMonmouth52 min
May 31, 9:28 PM EDTSevere Thunderstorm WarningLWXAllegany32 min

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.3 hours before the alert went out and 158 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 12:00Z on 2002-05-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 430 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2002-05-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.193958Sfc1 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
430 J/kg
Mixed-layer CIN
-126 J/kg
Mixed-layer LCL
1001 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
111 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 31, 2:45 PM EDTSevere Thunderstorm WatchSPCArmstrong, Bradford, Butler, Cameron, Carbon, Centre and 27 more5 hr
May 31, 5:00 PM EDTSevere Thunderstorm WatchSPCAllegheny, Armstrong, Beaver, Fayette, Greene, Indiana and 3 more6 hr

Nearby

Severe Thunderstorm Watches in Pennsylvania, 2002Severe Thunderstorm Watches in New Jersey, 2002Severe Thunderstorm Watches in Maryland, 2002Every severe thunderstorm watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.