Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 39, NWS State College, PA

July 9, 1990Centre County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 9, 1990, 1:34 PM EDT for Centre County, Pennsylvania. It was in force for 41 min. 4 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 9, 1990, 1:34 PM EDT (17:34 UTC)
Expired
Jul 9, 1990, 2:15 PM EDT
In force
41 min
Issued by
NWS State College, PA
Area
Whole counties

County Centre 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 9, 1:42 PM EDTThunderstorm Wind 0Centre, PA
Jul 9, 1:45 PM EDTThunderstorm Wind 0Centre, PA
Jul 9, 2:25 PM EDTThunderstorm Wind 0Centre, PA
Jul 9, 2:25 PM EDTThunderstorm Wind 0Centre, 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, 5.6 hours before the alert went out and 200 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 1990-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1312 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 1990-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 143 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
1312 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
1037 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
143 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
0.6
Supercell composite
5.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KHAR 091737 RRA
SVRHAR
PAC027-091815-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HARRISBURG PA
134 PM EDT MON JUL 9 1990
 
THE NATIONAL WEATHER SERVICE IN HARRISBURG HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  215 PM EDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN CENTRAL PENNSYLVANIA
          ...CENTRE
 
AT 130 PM EDT WEATHER SERVICE RADAR IN HARRISBURG INDICATED A LINE OF
THUNDERSTORMS...SOME HEAVY...OVER THE NORTH CENTRAL MOUNTAINS MOVING
EAST SOUTHEAST AT 25 MILES AN HOUR. THESE THUNDERSTORMS SHOULD ENTER
CENTRE COUNTY BY 200 PM EDT.
 
THIS IS A DANGEROUS STORM.  IF YOU ARE IN ITS PATH YOU SHOULD
PREPARE FOR DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...AND
DEADLY LIGHTNING.  PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT STAY AWAY FROM WINDOWS.
 
WSO HAR CRUZ

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 9, 12:18 PM EDT, 1 hour 16 minutes before
PAZ008-009-013-014-091620-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HARRISBURG PA.
1215 PM EDT MON JUL 9 1990

...POSSIBLE THUNDERSTORMS ENTERING THE LOWER SUSQUEHANNA VALLEY...

AT 1130 AM WEATHER SERVICE RADAR IN HARRISBURG INDICATED SCATTERED RAINSHOWERS
WITH EMBEDDED THUNDERSTORMS...SOME HEAVY... OVER NORTHWESTERN PENNSYLVANIA AND
THE NORTHERN  MOUNTAINS. THESE THUNDERSTORMS ARE SLOWLY MOVING EAST SOUTHEAST
AT 25 MILES AN HOUR AND WILL GRADUALLY CHANGE TO SOUTHEAST THIS AFTERNOON....
ALLOWING THEM TO ENTER INTO THE LOWER SUSQUEHANNA VALLEY JUST AFTER 200 PM EDT.

RAINFALL OF 1.50 INCHES HAS BEEN REPORTED OVER TIONESTA SINCE 1000 AM. IN
ADDITION...VERY HEAVY RAINS WERE REPORTED IN MEADVILLE. REMEMBER...IF
THREATENING WEATHER APPROACHES...SEEK SHELTER IMMEDIATELY.

STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOCAL TELEVISION OR RADIO STATION FOR
ANY FURTHER UPDATES ON THIS WEATHER SITUATION.

WSO HAR VGC
Special weather statement, Jul 9, 1:22 PM EDT, 12 minutes before
PAZ008-009-013-014-091730-
 SPECIAL WEATHER STATEMENT
 NATIONAL WEATHER SERVICE HARRISBURG PA.
 120 PM EDT MON JUL 9 1990

...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 900 PM EDT FOR THE LOWER
SUSQUEHANNA VALLEY...

AT 100 PM THE NATIONAL SEVERE STORMS FORECAST CENTER ISSUED A SEVERE
THUNDERSTORM WATCH FOR MUCH OF PENNSYLVANIA TO INCLUDE THE LOWER SUSQUEHANNA
VALLEY.  PERSONS LIVING IN CENTRE...FULTON...HUNTINGDON...JUNIATA...MIFFLIN...
NORTHUMBERLAND...MONTOUR...SYNDER...UNION...ADAMS...CUMBERLAND...DAUPHIN...
FRANKLIN...LANCASTER...LEBANON...PERRY...AND YORK COUNTIES SHOULD KEEP AN EYE
ON THE SKY FOR THREATENING THUNDERSTORMS...AND LISTEN FOR FORECAST UPDATES AND
POSSIBLE WARNINGS ON THE CURRENT WEATHER SITUATION.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR
SEVERE THUNDESTORMS IN AND CLOSE TO THE WATCH AREA. IT'S BEST TO TAKE SHELTER
INSIDE A STRONG BUILDING AND AWAY FROM GLASS. IF YOU ARE CAUGHT OUTSIDE...BE
AWARE THAT LIGHTNING IS AS MUCH A HAZARD AS HIGH WIND. AVOID ISOLATED TREES AND
METAL OBJECTS.

WSO HAR VGC

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 2:04 PM EDTSevere Thunderstorm WarningCTPCentre, Union56 min
Jul 9, 2:04 PM EDTSevere Thunderstorm WarningCTPSnyder56 min
Jul 9, 2:42 PM EDTSevere Thunderstorm WarningCTPCentre, Mifflin, Snyder, Union48 min
Jul 9, 3:09 PM EDTSevere Thunderstorm WarningCTPCarbon, Monroe, Northampton66 min
Jul 9, 4:07 PM EDTSevere Thunderstorm WarningCTPNorthampton38 min
Jul 9, 4:31 PM EDTSevere Thunderstorm WarningCTPLancaster, York44 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1990Every severe thunderstorm warning in 1990

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.