Alert archive / Pennsylvania / Tornado Watches in 2002

Tornado Watch 95

April 15, 2002Chautauqua County, New York; 11 counties in Ohio; 12 counties in Pennsylvania

The Storm Prediction Center issued this tornado watch at Apr 15, 2002, 6:15 PM EDT for Chautauqua County, New York; 11 counties in Ohio; 12 counties in Pennsylvania. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 15, 2002, 6:15 PM EDT (22:15 UTC)
Expired
Apr 15, 2002, 10:00 PM EDT
In force
4 hr
Issued by
the Storm Prediction Center
All 24 counties

Chautauqua County, NY, Ashtabula County, OH, Carroll County, OH, Columbiana County, OH, Cuyahoga County, OH, Geauga County, OH, Lake County, OH, Mahoning County, OH, Portage County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Armstrong County, PA, Beaver County, PA, Butler County, PA, Clarion County, PA, Crawford County, PA, Erie County, PA, Forest County, PA, Jefferson County, PA, Lawrence County, PA, Mercer County, PA, Venango County, PA, Warren County, PA

The radar

The Cleveland radar (KCLE), 102 km from the middle of the area, began a volume at 22:15 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

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

IssuedProductOfficeCountiesLasted
Apr 15, 6:15 PM EDTSevere Thunderstorm WarningPBZVenango60 min
Apr 15, 6:21 PM EDTTornado WarningCLETrumbull54 min
Apr 15, 6:24 PM EDTTornado WarningPBZMercer36 min
Apr 15, 6:30 PM EDTSevere Thunderstorm WarningCLECrawford30 min
Apr 15, 6:32 PM EDTFlash Flood WarningCLECrawford118 min
Apr 15, 6:44 PM EDTSevere Thunderstorm WarningPBZClarion61 min
Apr 15, 6:50 PM EDTSevere Thunderstorm WarningCLEMahoning55 min
Apr 15, 6:59 PM EDTSevere Thunderstorm WarningPBZMercer46 min
Apr 15, 7:12 PM EDTSevere Thunderstorm WarningPBZVenango48 min
Apr 15, 7:14 PM EDTSevere Thunderstorm WarningPBZJefferson46 min
Apr 15, 7:18 PM EDTSevere Thunderstorm WarningPBZButler27 min
Apr 15, 7:23 PM EDTFlash Flood WarningPBZMercer3 hr
Apr 15, 7:35 PM EDTTornado WarningPBZButler25 min
Apr 15, 7:46 PM EDTSevere Thunderstorm WarningPBZClarion44 min
Apr 15, 7:56 PM EDTSevere Thunderstorm WarningPBZVenango19 min
Apr 15, 7:58 PM EDTSevere Thunderstorm WarningPBZJefferson32 min
Apr 15, 8:16 PM EDTFlash Flood WarningPBZJefferson3 hr
Apr 15, 8:20 PM EDTSevere Thunderstorm WarningPBZArmstrong40 min
Apr 15, 8:25 PM EDTFlash Flood WarningPBZClarion3 hr
Apr 15, 8:28 PM EDTSevere Thunderstorm WarningPBZClarion47 min

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 10.3 hours before the alert went out and 121 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 2002-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 67 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 2002-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 192 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
67 J/kg
Mixed-layer CIN
-30 J/kg
Mixed-layer LCL
620 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
192 m²/s²
0-3 km storm-relative helicity
243 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 152210
SEL5  
SPC WW 152202
NYZ000-OHZ000-PAZ000-LEZ000-160200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 95
STORM PREDICTION CENTER NORMAN OK
602 PM EDT MON APR 15 2002

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
                             
   EASTERN OHIO                               
   NORTHWEST PENNSYLVANIA                       
   LAKE ERIE                          

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 615 PM UNTIL 1000
PM EDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 60 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 50 STATUTE MILES EITHER SIDE OF
A LINE FROM 15 MILES WEST NORTHWEST OF AKRON OHIO TO 35 MILES NORTH
OF DUBOIS PENNSYLVANIA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

DISCUSSION...A FEW SUPERCELLS EXPECTED TO CONTINUE DEVELOPING IN
REGION OF DEEP VEERING WIND PROFILES INVOF DIFFUSE WARM FRONT OVER
FAR NE OH/WRN PA.  ABSENCE OF LINEAR FORCING AND RELATIVELY HIGH
BOUNDARY LAYER RELATIVE HUMIDTIES SUGGEST THREAT FOR LOW LEVEL
STORM ROTATION/POSSIBLE TORNADOES...IN ADDITION TO LARGE HAIL.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 50 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 30035.

...CORFIDI

414,0815 422,0790 405,0783 401,0812

WWUS20 KWNS 152210
SEL5  
SPC WW 152202
NYZ000-OHZ000-PAZ000-LEZ000-160200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 95
STORM PREDICTION CENTER NORMAN OK
602 PM EDT MON APR 15 2002

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
                             
   EASTERN OHIO                               
   NORTHWEST PENNSYLVANIA                       
   LAKE ERIE                          

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 615 PM UNTIL 1000
PM EDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 60 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 50 STATUTE MILES EITHER SIDE OF
A LINE FROM 15 MILES WEST NORTHWEST OF AKRON OHIO TO 35 MILES NORTH
OF DUBOIS PENNSYLVANIA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

DISCUSSION...A FEW SUPERCELLS EXPECTED TO CONTINUE DEVELOPING IN
REGION OF DEEP VEERING WIND PROFILES INVOF DIFFUSE WARM FRONT OVER
FAR NE OH/WRN PA.  ABSENCE OF LINEAR FORCING AND RELATIVELY HIGH
BOUNDARY LAYER RELATIVE HUMIDTIES SUGGEST THREAT FOR LOW LEVEL
STORM ROTATION/POSSIBLE TORNADOES...IN ADDITION TO LARGE HAIL.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 50 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 30035.

...CORFIDI

414,0815 422,0790 405,0783 401,0812

Nearby

Tornado Watches in Pennsylvania, 2002Tornado Watches in Ohio, 2002Tornado Watches in New York, 2002Every tornado 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.