Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 97, NWS Cleveland, OH

July 6, 1991Venango County, Pennsylvania

NWS Cleveland, OH issued this severe thunderstorm warning at Jul 6, 1991, 3:15 PM EDT for Venango County, Pennsylvania. It was in force for 60 min. 1 report 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
Jul 6, 1991, 3:15 PM EDT (19:15 UTC)
Expired
Jul 6, 1991, 4:15 PM EDT
In force
60 min
Issued by
NWS Cleveland, OH
Area
Whole counties

County Venango County, PA

What was reported inside it

TimeReportWhereRemark
Jul 6, 4:00 PM EDTThunderstorm Wind 0Venango, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 7.3 hours before the alert went out and 191 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, Buffalo Intl Airport, NY at 12:00Z on 1991-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 687 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, Buffalo Intl Airport, NY at 12:00Z on 1991-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 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
687 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
876 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
125 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.9

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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, Jul 6, 1:14 PM EDT, 2 hours 1 minute before
OHZ004-007-061900-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE AKRON CANTON OH
112 PM EDT SAT JUL 6 1991

THUNDERSTORMS...PRODUCING VERY HEAVY RAIN...HAD DEVELOPED OVER
PARTS OF NORTHEAST OHIO EARLY THIS AFTERNOON.

AT 1:10 PM WEATHER RADAR INDICATED THE HEAVIEST RAINFALL OVER
CENTRAL PORTAGE COUNTY.

WIDELY SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP THE
REMAINDER OF THIS AFTERNOON AND EVENING OVER EASTERN OHIO.
SOME OF THESE STORMS WILL BE CAPABLE OF DROPPING OVER AN INCH OF
RAIN IN LESS THAN AN HOUR.

RAINFALL OF THIS INTENSITY WILL CAUSE BRIEF PONDING OF WATER ON ROADWAYS
AND IN LOW LYING AREAS. MOTORISTS SHOULD ALSO BE ALERT FOR GREATLY
REDUCED VISIBILITIES.
THOMPSON
Special weather statement, Jul 6, 2:31 PM EDT, 44 minutes before
OHZALL-062100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CLEVELAND OHIO
230 PM EDT FRI JUL 5 1991

...SEVERE THUNDERSTORM WATCH IN EFFECT FOR PARTS OF NORTHEAST AND
EASTCENTRAL OHIO UNTIL 1000 PM EDT...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR PARTS OF NORTHEAST AND EASTCENTRAL OHIO UNTIL 1000 PM EDT. SOME
CITIES INCLUDED IN THIS WATCH ARE AKRON...CANTON...YOUNGSTOWN...
ASHTABULA...AND STEUBENVILLE.

AT 230 PM EDT RADAR SHOWED SCATTERED THUNDERSTORMS LINED UP FROM JUST
EAST OF AKRON TO THE YOUNGSTOWN AREA TO THE FRANKLIN AREA OF
PENNSYLVANIA. THE THUNDERSTORMS WERE POPPING UP AND DOWN RATHER
QUICKLY AS THEY MOVED EAST AT ABOUT 30 MPH.

ANY OF THE THUNDERSTORMS OVER NORTHEAST AND EASTCENTAL OHIO CAN BECOME
SEVERE AND PRODUCE DAMAGING WINDS AND LARGE HAIL. VERY HEAVY DOWNPOURS
OF RAIN CAN ALSO OCCUR WITH TEMPORARY URBAN AND DRAINING SYSTEM
FLOODING THE RESULT.

THE REMAINDER OF OHIO ALSO HAS A CHANCE OF SHOWERS AND THUNDERSTORMS
FOR THIS AFTERNOON THROUGH TONIGHT.
KAPELA
Special weather statement, Jul 6, 2:36 PM EDT, 39 minutes before
OHZALL-062100-

SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE CLEVELAND OHIO
230 PM EDT SAT JUL 6 1991

...SEVERE THUNDERSTORM WATCH IN EFFECT FOR PARTS OF NORTHEAST AND
EASTCENTRAL OHIO UNTIL 1000 PM EDT...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR PARTS OF NORTHEAST AND EASTCENTRAL OHIO UNTIL 1000 PM EDT. SOME
CITIES INCLUDED IN THIS WATCH ARE CANTON...YOUNGSTOWN...ASHTABULA...
AND STEUBENVILLE.

AT 230 PM EDT RADAR SHOWED SCATTERED THUNDERSTORMS LINED UP FROM JUST
EAST OF AKRON TO THE YOUNGSTOWN AREA TO THE FRANKLIN AREA OF
PENNSYLVANIA. THE THUNDERSTORMS WERE POPPING UP AND DOWN RATHER
QUICKLY AS THEY MOVED EAST AT ABOUT 30 MPH.

ANY OF THE THUNDERSTORMS OVER NORTHEAST AND EASTCENTAL OHIO CAN BECOME
SEVERE AND PRODUCE DAMAGING WINDS AND LARGE HAIL. VERY HEAVY DOWNPOURS
OF RAIN CAN ALSO OCCUR WITH TEMPORARY URBAN AND DRAINING SYSTEM
FLOODING THE RESULT.

THE REMAINDER OF OHIO ALSO HAS A CHANCE OF SHOWERS AND THUNDERSTORMS
FOR THIS AFTERNOON THROUGH TONIGHT.

KAPELA
CORRECTED FOR DATE AND CITIES INCLUDED IN WATCH
Special weather statement, Jul 6, 2:55 PM EDT, 20 minutes before
PAZ003-062000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ERIE, PA
250 PM EDT SAT JUL 06 1991

...THUNDERSTORMS PRODUCING HEAVY RAIN AND INTENSE LIGHTNING OVER SOUTHERN
VENANGO COUNTY OF NORTHWEST PENNSYLVANIA...
...SEVERE THUNDERSTORM WATCH UNTIL 1000 PM FOR ALL OF WESTERN PENNSYLVANIA
EXCEPT ERIE COUNTY...

AT 240 PM EDT WEATHER RADAR SHOWED A LINE OF THUNDERSTORMS EXTENDING FROM
YOUNGSTOWN OHIO EASTWARD TO DUBOIS TO SOUTHERN CAMERON COUNTY.  THE LINE
OF THUNDERSTORMS WAS DRIFTING SLOWLY TO THE SOUTH.  THE THUNDERSTORMS CELLS
WITHIN THE LINE WERE MOVING TO THE EAST AT ABOUT 30 MILES AN HOUR.

THE STATE POLICE IN VENANGO COUNTY REPORTED VERY HEAVY RAIN AND INTENSE
LIGHTNING NEAR INTERSTATE 80 IN SOUTHERN VENANGO COUNTY.

OTHER THUNDERSTORMS CELLS MOVING EAST FROM MERCER COUNTY WILL MOVE THROUGH
SOUTHERN VENANGO COUNTY WITHIN THE NEXT HOUR.  THESE THUNDERSTORMS WILL
CONTINUE TO BRING VERY HEAVY RAIN AND DANGEROUS LIGHTNING TO SOUTHERN
VENANGO COUNTY.  AS THESE STORMS CONTINUE TO MOVE ACROSS THE SAME AREAS...
SOME FLOODING MAY DEVELOP ALONG SMALL STREAMS AND LOW LYING AREAS.
TRAVELERS ALONG INTERSTATE 80 SHOULD BE PREPARED FOR VERY HEAVY DOWNPOURS THAT
MAY CAUSE PONDING OF WATER ON ROAD SURFACES  AND POOR VISIBILITY.

STAY TUNED TO NOAA WEATHER RADIO FOR MORE UPDATES OR POSSIBLE WARNINGS.

TJP

The office that day

Everything else NWS Cleveland, OH issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 3:05 PM EDTSevere Thunderstorm WarningCLEMahoning55 min
Jul 6, 4:13 PM EDTFlash Flood WarningCLEMahoning62 min
Jul 6, 4:13 PM EDTSevere Thunderstorm WarningCLEMahoning62 min
Jul 6, 5:18 PM EDTFlash Flood WarningCLEMahoning57 min
Jul 6, 5:18 PM EDTSevere Thunderstorm WarningCLEMahoning57 min
Jul 6, 2:18 PM EDTSevere Thunderstorm WarningCLEMercer57 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1991Every severe thunderstorm warning in 1991

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.