Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 45, NWS Pittsburgh, PA

June 25, 1997Mercer County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Jun 25, 1997, 8:56 PM EDT for Mercer County, Pennsylvania. It was in force for 64 min. 3 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
Jun 25, 1997, 8:56 PM EDT (00:56 UTC)
Expired
Jun 25, 1997, 10:00 PM EDT
In force
64 min
Issued by
NWS Pittsburgh, PA
Area
Whole counties

County Mercer County, PA

The radar

The Pittsburgh radar (KPBZ), 86 km from the middle of the area, began a volume at 00:55 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
Jun 25, 9:05 PM EDTThunderstorm WindJamestown, PATrees were downed by thunderstorm winds near Jamestown.
Jun 25, 9:10 PM EDTThunderstorm WindGreenville, PASevere thunderstorm winds downed trees and large branches in Greenville.
Jun 25, 9:21 PM EDTHail 0.75Sandy Lake, PA

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 nearest sounding before it

Pittsburgh, PA (KPIT), launched 00:00Z, 0.9 hours before the alert went out and 100 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 00:00Z on 1997-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1973 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 00:00Z on 1997-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.1939Sfc1 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
1973 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1287 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
138 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.9

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPIT 260054 RRA
SVRPIT
PAC085-260200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
856 PM EDT WED JUN 25 1997
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1000 PM EDT
FOR THE FOLLOWING LOCATION...
 
IN NORTHWEST PENNSYLVANIA
 
   ...MERCER COUNTY
 
AT 856 PM DOPPLER RADAR SHOWED A SEVERE THUNDERSTORM MOVING INTO
NORTHWEST MERCER COUNTY NEAR JAMESTOWN AND GREENVILLE. THE STORM WAS
MOVING EAST ABOUT 25 MPH. THE STORM WILL MOVE TO NEAR INTERSTATE 79 NEAR
WILLIAMS CORNERS BY 915 PM. EXPECT DAMAGING WINDS WITH THIS STORM WHICH
CAN TOPPLER TREES AND POWER LINES.
 
 
KANE

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.

In the hours before

Special weather statement, Jun 25, 6:35 PM EDT, 2 hours 21 minutes before
PAZ008-009-OHZ048-057-260400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
635 PM EDT WED JUN 25 1997

...THE NATIONAL WEATHER SERVICE IN PITTSBURGH SAYS...

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR COSHOCTON AND MUSKINGUM
COUNTIES IN EAST CENTRAL OHIO UNTIL 11 PM. THUNDERSTORMS TO THE WEST
OF THIS AREA WILL MOVE INTO COSHOCTON AND MUSKINGUM COUNTIES AFTER
9 PM.

A SEVERE THUNDERSTORM WATCH IS ALSO IN EFFECT FOR FOREST AND VENANGO
COUNTIES IN NORTHERN PENNSYLVANIA UNTIL MIDNIGHT. THUNDERSTORMS
ALREADY EXIST JUST TO THE NORTH OF FOREST AND VENANGO COUNTIES. THESE
STORMS ARE MOVING EAST. OTHER STORMS WILL LIKELY AFFECT FOREST AND
VENANGO COUNTIES AFTER 8 PM.

A FLASH FLOOD WATCH MAY BE NEEDED LATER THIS EVENING FOR NORTHERN
PENNSYLVANIA. IF MORE THAN ONE AND A HALF INCHES OF RAIN SHOULD FALL
IN AN HOUR...FLOODING WILL BEGIN.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 25, 8:31 PM EDTSevere Thunderstorm WarningPBZForest59 min
Jun 25, 9:20 PM EDTSevere Thunderstorm WarningPBZVenango55 min
Jun 25, 9:32 PM EDTFlash Flood WarningPBZMercer, Venango118 min
Jun 25, 9:32 PM EDTFlash Flood WarningPBZForest118 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1997Every severe thunderstorm warning in 1997

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.