Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1989

Severe Thunderstorm Warning 21, NWS Pittsburgh, PA

July 7, 1989Armstrong County, Indiana County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Jul 7, 1989, 6:51 PM EDT for Armstrong County, Indiana County, Pennsylvania. It was in force for 69 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
Jul 7, 1989, 6:51 PM EDT (22:51 UTC)
Expired
Jul 7, 1989, 8:00 PM EDT
In force
69 min
Issued by
NWS Pittsburgh, PA
Area
Whole counties

Counties Armstrong County, PA, Indiana County, PA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
Jul 7, 7:05 PM EDTThunderstorm Wind 0Indiana, PA
Jul 7, 7:15 PM EDTThunderstorm Wind 0Armstrong, PA
Jul 7, 7:30 PM EDTHail 0.75Indiana, 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

Pittsburgh, PA (KPIT), launched 12:00Z, 10.9 hours before the alert went out and 78 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 1989-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 18 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 1989-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 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
18 J/kg
Mixed-layer CIN
-132 J/kg
Mixed-layer LCL
1092 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
14 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 
TTAA00 KPIT 072254
SVRPIT
PAC005-013-021-063-080000-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
651 PM EDT FRI JUL 7 1989
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  800 PM EDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN WEST PENNSYLVANIA
          ...ARMSTRONG...BLAIR...INDIANA...CAMBRIA
 
PITTSBURGH WEATHER RADAR INDICATES HEAVY THUNDERSTORMS EXTENDING FROM
BUTLER AND CLARION COUNTIES EXTENDING EAST INTO THE CENTRAL AND
SOUTHERN MOUNTAINS OF WESTERN PENNSYLVANIA. THE THUNDERSTORMS ARE
MOVING SOUTHEAST AT 35 MPH.
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...8DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

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 7, 2:45 PM EDT, 4 hours 6 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH, PA
244 PM EDT FRI JUL 07 1989

...THUNDERSTORMS WITH STRONG GUSTY WINDS AND HEAVY DOWNPOURS FOR THE
   REMAINDER OF AFTERNOON AND EVENING ACROSS WESTERN PENNSYLVANIA AND
   THE NORTHERN PANHANDLE OF WEST VIRGINIA...

FOR THE REMAINDER OF THIS AFTERNOON AND EVENING THERE IS A DOUBLE
THREAT OF SEVERE WEATHER IN WESTERN PENNSYLVANIA AND THE NORTHERN
PANHANDLE OF WEST VIRGINIA. WE COULD HAVE THUNDERSTORMS WITH DAMAGING
WINDS AND DANGEROUS LIGHTNING AND ALSO SLOW MOVING THUNDERSTORMS COULD
DROP A LOT OF RAIN IN A SHORT PERIOD OF TIME. LOW LYING AND POOR
DRAINAGE AREAS ARE ESPECIALLY VULNERABLE TO FLOODING FROM HEAVY
DOWNPOURS.

RESIDENTS SHOULD BE ON THE LOOKOUT FOR BOTH SEVERE THUNDERSTORMS
AND ALSO HEAVY DOWNPOURS ASSOCIATED WITH THESE STORMS THIS
AFTERNOON AND EVENING. NEVER EVER DRIVE THROUGH FLOODED ROADWAYS.
YOUR CAR FEELS VERY SAFE AND VERY HEAVY...BUT IT IS ALSO
VERY BUOYANT AND WILL FLOAT WITH AS LITTLE AS 2 FEET OF WATER.

A COLD FRONT MOVING FROM NORTH TO SOUTH ACROSS WESTERN PENNSYLVANIA
AND THE NORTHERN PANHANDLE OF WEST VIRGINIA WILL PRODUCE THESE
THUNDERSTORMS. THE FRONT WILL MOVE SOUTH OF PENNSYLVANIA LATE THIS
EVENING AND END THE THREAT OF SEVERE STORMS.

STAIRS/GIORDANO
Special weather statement, Jul 7, 4:24 PM EDT, 2 hours 27 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH, PA
425 PM EDT FRI JUL 07 1989

...THUNDERSTORMS WITH HEAVY DOWNPOURS MOVING INTO BUTLER..ARMSTRONG
   AND CLARION COUNTIES...

A LINE OF THUNDERTORMS EXTENDING FROM TIONESTA IN ELK COUNTY TO MERCER
IN MERCER COUNTY IS MOVING SOUTHEAST AT 30 MPH. THESE THUNDERSTORMS
WILL MOVE THROUGH BUTLER...ARMSTRONG..CLARION AND JEFFERSON COUNTIES IN
WESTERN PENNSYLVANIA BETWEEN 430 AND 630 PM.

SOME OF THESE THUNDERSTORMS MAY BE ACCOMPANIED BY STRONG GUSTY WINDS..
HAIL..LOCALLY HEAVY DOWNPOURS AND DANGEROUS LIGHTNING.

SOME OF THE LOCALLY HEAVY DOWNPOURS MAY PRODUCE ENOUGH RAIN TO CAUSE
POOR DRAINAGE FLOODING.

IF THREATENING WEATHER APPROACHES...GO TO A SAFE PLACE IMMEDIATELY.
DO NOT DRIVE THROUGH FLOODED AREAS.
DAVIS/SISK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 4:37 PM EDTSevere Thunderstorm WarningPBZClarion, Jefferson68 min
Jul 7, 5:41 PM EDTSevere Thunderstorm WarningPBZClearfield, Jefferson64 min
Jul 7, 6:14 PM EDTSevere Thunderstorm WarningPBZArmstrong, Butler, Clarion61 min
Jul 7, 6:51 PM EDTSevere Thunderstorm WarningPBZBlair, Cambria69 min
Jul 7, 7:57 PM EDTSevere Thunderstorm WarningPBZCambria, Indiana, Westmoreland63 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1989Every severe thunderstorm warning in 1989

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.