Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 27, NWS State College, PA

September 17, 1987Adams County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Sep 17, 1987, 11:23 PM EDT for Adams County, Pennsylvania. It was in force for 57 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
Sep 17, 1987, 11:23 PM EDT (03:23 UTC)
Expired
Sep 18, 1987, 12:20 AM EDT
In force
57 min
Issued by
NWS State College, PA
Area
Whole counties

County Adams 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
Sep 17, 11:30 PM EDTThunderstorm Wind 0Adams, 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 3.4 hours before the alert went out and 104 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, Washington/Dulle, VA at 00:00Z on 1987-09-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1181 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, Washington/Dulle, VA at 00:00Z on 1987-09-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
1181 J/kg
Mixed-layer CIN
-62 J/kg
Mixed-layer LCL
1046 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.8

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, Sep 17, 5:56 PM EDT, 5 hours 27 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HARRISBURG PA.
550 PM EDT THU SEP 17 1987

...VERY HEAVY THUNDERSTORMS CONTINUE MOVING RADIPLY EAST FROM THE
WESTERN MOUNTAINS THROUGH THE SUSQUEHANNA VALLEY...

AT 540 PM EDT THE NATIONAL WEATHER SERVICE RADAR WAS OBSERVING TWO
CLUSTERS OF VERY HEAVY THUNDERSTORMS.  THE FIRST CLUSTER WAS
LOCATED FROM COLUMBIA COUNTY SOUTH INTO SCHUYLKILL...LEBANON AND
DAUPHIN COUNTIES.

A SECOND CLUSTER OF VERY HEAVY THUNDERSTORMS WAS LOCATED IN MIFFLIN
AND HUNTINGDON COUNTIES.

AS THESE THUNDERSTORMS MOVE EAST AT 25 TO 30 MPH...THEY WILL BE
ACCOMPANIED BY BRIEF HEAVY DOWNPOURS...POSSIBLY CAUSING FLOODING IN
AREAS OF POOR DRAINAGE...GUSTY SURFACE WINDS AND POSSIBLY SMALL HAIL.

RESIDENTS SHOULD BE ALERT FOR RAPIDLY CHANGING WEATHER CONDITIONS
UNTIL 700 PM EDT.
WSO HAR FITZSIMMONS
Special weather statement, Sep 17, 6:59 PM EDT, 4 hours 24 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HARRISBURG PA.
655 PM EDT THU SEP 17 1987

...VERY HEAVY THUNDERSTORMS OCCURRING OVER THE SOUTH CENTRAL MOUNTAINS
AND SOUTH CENTRAL PENNSYLVANIA...

AT 650 PM EDT THE NATIONAL WEATHER SERVICE RADAR WAS INDICATING AN AREA
OF VERY HEAVY THUNDERSTORMS EXTENDING FROM CENTER COUNTY SOUTH INTO
HUNTINGDON COUNTY.  THE STRONGEST STORMS WERE LOCATED JUST EAST OF
RAYSTOWN LAKE AND BETWEEN BELLEVILLE AND LEWISTON IN MIFFLIN COUNTY.

AS THESE THUNDERSTORMS CONTINUE TO THE EAST AT 25 TO 30 MPH...THEY
WILL BE ACCOMPANIED BY BRIEF HEAVY DOWNPOURS POSSIBLY CAUSING FLOODING
IN AREAS OF POOR DRAINAGE...GUSTY SURFACE WINDS AND FREQUENT LIGHTNING.

RESIDENTS IN THESE COUNTIES AND IN THE COUNTIES OF UNION...SYNDER...
JUNIATA AND PERRY COUNTIES CAN EXPECT RAPIDLY CHANGING WEATHER CONDITION
UNTIL 800 PM EDT

WSO HAR FITZSIMMONS
Special weather statement, Sep 17, 7:04 PM EDT, 4 hours 19 minutes before
SPECIAL WEATHER STATEMENT...CORRECTION
NATIONAL WEATHER SERVICE HARRISBURG PA.
655 PM EDT THU SEP 17 1987

...VERY HEAVY THUNDERSTORMS OCCURRING OVER THE SOUTH CENTRAL MOUNTAINS
AND SOUTH CENTRAL PENNSYLVANIA...

AT 650 PM EDT THE NATIONAL WEATHER SERVICE RADAR WAS INDICATING AN AREA
OF VERY HEAVY THUNDERSTORMS EXTENDING FROM CENTER COUNTY SOUTH INTO
HUNTINGDON COUNTY.  THE STRONGEST STORMS WERE LOCATED JUST EAST OF
RAYSTOWN LAKE AND BETWEEN BELLEVILLE AND LEWISTON IN MIFFLIN COUNTY.

AS THESE THUNDERSTORMS CONTINUE TO THE EAST AT 25 TO 30 MPH...THEY
WILL BE ACCOMPANIED BY BRIEF HEAVY DOWNPOURS POSSIBLY CAUSING FLOODING
IN AREAS OF POOR DRAINAGE...GUSTY SURFACE WINDS AND FREQUENT LIGHTNING.

RESIDENTS IN THESE COUNTIES AND IN THE COUNTIES OF UNION...SYNDER...
JUNIATA AND PERRY CAN EXPECT RAPIDLY CHANGING WEATHER CONDITION
UNTIL 800 PM EDT.

WSO HAR FITZSIMMONS
Special weather statement, Sep 17, 8:19 PM EDT, 3 hours 4 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HARRISBURG PA.
810 PM EDT THU SEP 17 1987

...CLUSTER OF INTENSE THUNDERSTORMS MOVING ACROSS CUMBERLAND COUNTY...

AT 815 PM EDT THE NATIONAL WEATHER SERVICE RADAR WAS OBSERVING AN
INTENSE CLUSTER OF THUNDERSTORMS MOVING ACROSS NORTHERN CUMBERLAND COUNTY.
SPOTTERS IN THE NEWVILLE AREA HAVE REPORTED PEA SIZE HAIL REDUCING
VISIBILITIES TO NEAR ZERO.

THIS STORM WILL CONTINUE MOVING EAST AT 25 TO 30 MPH AND WILL PRODUCE
VERY HEAVY RAIN POSSIBLY CAUSING FLOODING IN AREAS OF POOR DRAINAGE...
GUSTY SURFACE WINDS AND HAIL.

RESIDENTS IN CUMBERLAND COUNTY SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS UNTIL 900 PM EDT.

END
WSO HAR 9FITZSIMMONS

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 17, 8:54 PM EDTSevere Thunderstorm WarningCTPCumberland56 min
Sep 17, 9:04 PM EDTFlash Flood WarningCTPCumberland3 hr
Sep 18, 5:26 PM EDTSevere Thunderstorm WarningCTPLancaster64 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1987Every severe thunderstorm warning in 1987

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.