Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 935

September 27, 20035 states

The Storm Prediction Center issued this severe thunderstorm watch at Sep 27, 2003, 4:05 PM EDT for 5 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Sep 27, 2003, 4:05 PM EDT (20:05 UTC)
Expired
Sep 27, 2003, 9:00 PM EDT
In force
5 hr
Issued by
the Storm Prediction Center
All 52 counties

Allegany County, MD, Garrett County, MD, Washington County, MD, Cayuga County, NY, Chemung County, NY, Cortland County, NY, Onondaga County, NY, Ontario County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wayne County, NY, Yates County, NY, Bedford County, PA, Blair County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clearfield County, PA, Clinton County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lycoming County, PA, Mifflin County, PA, Potter County, PA, Somerset County, PA, Tioga County, PA, Union County, PA, Augusta County, VA, City of Harrisonburg, VA, City of Staunton, VA, City of Winchester, VA, Frederick County, VA, Highland County, VA, Page County, VA, Rockingham County, VA, Shenandoah County, VA, Warren County, VA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Mineral County, WV, Morgan County, WV, Pendleton County, WV, Pocahontas County, WV, Randolph County, WV, Tucker County, WV

The radar

The State College radar (KCCX), 92 km from the middle of the area, began a volume at 20:05 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

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

IssuedProductOfficeCountiesLasted
Sep 27, 5:20 PM EDTFlash Flood WarningLWXAllegany4 hr
Sep 27, 5:39 PM EDTFlash Flood WarningCTPBedford3 hr
Sep 27, 6:18 PM EDTFlash Flood WarningCTPBlair117 min
Sep 27, 6:47 PM EDTFlash Flood WarningCTPCentre, Fulton, Huntingdon3 hr
Sep 27, 8:02 PM EDTFlash Flood WarningCTPBlair118 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 8.1 hours before the alert went out and 143 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, Pittsburgh, PA at 12:00Z on 2003-09-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 54 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, Pittsburgh, PA at 12:00Z on 2003-09-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 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
54 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
683 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
119 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
Sep 27, 2:22 PM EDTMesoscale DiscussionSPCFrederick, Washington113 min
Sep 27, 6:52 PM EDTMesoscale DiscussionSPCAllegany, Washington53 min
Sep 27, 1:58 AM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Cayuga, Erie, Genesee, Livingston and 9 more62 min
Sep 27, 2:35 AM EDTTornado WatchSPCAllegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 6 more5 hr
Sep 27, 6:39 AM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Chautauqua, Erie, Livingston, Wyoming96 min
Sep 27, 12:06 AM EDTMesoscale DiscussionSPCAllegheny, Armstrong, Beaver, Butler, Crawford, Lawrence and 3 more84 min
Sep 27, 12:40 AM EDTTornado WatchSPCBeaver, Butler, Crawford, Forest, Lawrence, Mercer and 2 more5 hr
Sep 27, 3:37 AM EDTMesoscale DiscussionSPCAllegheny, Armstrong, Beaver, Butler, Cambria, Cameron and 17 more113 min
Sep 27, 5:15 AM EDTMesoscale DiscussionSPCBeaver, Crawford, Lawrence, Mercer, Venango, Warren60 min
Sep 27, 11:42 AM EDTMesoscale DiscussionSPCDickenson, Lee, Russell, Scott, Wise, City of Norton108 min
Sep 27, 2:41 PM EDTMesoscale DiscussionSPCAlleghany, Bedford, Bland, Botetourt, Carroll, Craig and 17 more2 hr

Nearby

Severe Thunderstorm Watches in Pennsylvania, 2003Severe Thunderstorm Watches in New York, 2003Severe Thunderstorm Watches in Virginia, 2003Every severe thunderstorm watch in 2003

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.