Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 128, NWS State College, PA

August 5, 1997Franklin County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Aug 5, 1997, 6:41 PM EDT for Franklin County, Pennsylvania. It was in force for 64 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
Aug 5, 1997, 6:41 PM EDT (22:41 UTC)
Expired
Aug 5, 1997, 7:45 PM EDT
In force
64 min
Issued by
NWS State College, PA
Area
Whole counties

County Franklin County, PA

The radar

The Sterling radar (KLWX), 108 km from the middle of the area, began a volume at 22:40 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
Aug 5, 6:50 PM EDTHail 0.75Dry Run, 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.7 hours before the alert went out and 112 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 12:00Z on 1997-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 1997-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -76 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1203 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
-76 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 KCTP 052243 RRA
SVRCTP
PAC055-052345-

BULLETIN- IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
641 PM EDT TUE AUG 5 1997

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 745 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN SOUTH CENTRAL PENNSYLVANIA

   ...FRANKLIN COUNTY
 
AT 639 PM EDT...A SEVERE THUNDERSTORM WAS INDICATED BY STATE
COLLEGE DOPPLER RADAR 18 MILES NORTHWEST OF CHAMBERSBURG OR IN THE
VICINITY OF DRY RUN MOVING SOUTH AT 15 MPH.

THE STORM WILL PASS NEAR THE FOLLOWING LOCATIONS...
DRY RUN                          BY 639 PM EDT
SPRING RUN                       BY 639 PM EDT
ROXBURY                          BY 655 PM EDT
UPPER STRASBURG                  BY 705 PM EDT
LETTERKENNY ARMY DEPOT           BY 720 PM EDT
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VE,RY HEAVY RAIN AND
DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.  STAY
INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

FITZGERALD/WINTHER

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.

NWS State College, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 5, 12:45 PM EDT, 5 hours 56 minutes earlier.

Area forecast discussion, Aug 5, 12:45 PM EDT, 5 hours 56 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1245 PM EDT TUE AUG 5 1997

...SUGGESTIONS...

MAY NEED ISOLATED SHOWERS/STORMS INTO EARLY EVENING ALL ZNS.

MAYBE RAISE MIN TEMPS TONIGHT A SHADE...ALL ZNS.

...DISCUSSION...

STRONG CYCLONIC FLOW AND JET MAX...ALONG WITH COLD AIR ALOFT AND
HEATING HAS TRIGGERED SOME STORMS.  STORMS COULD OCCUR JUST ABOUT
ANYWHERE TO HEATING IS LOST.  SOME SMALL HAIL POSSIBLE...MOST
LIKELY SHOULD NOT BE SEVERE FOR THE MOST PART.

LACK OF DRY AIR MOVING IN...AND TENDENCY FOR MODELS TO HOLD LOW
LEVEL RH IN LONGER...MINS MAY NOT GET REAL LOW.  STILL SHOULD
CLEAR LATER.

FOR WED...NGM HAS ANOTHER VORT MAX AND STILL COLD ALOFT WITH
CYCLONIC FLOW.  THUS SC/CU LIKELY...MAYBE EVEN A RW-.  TEMPS
OK...BUT OK IF ONE WANTS TO GO A SHADE HIGHER.

LONG TERM

LOOKS LIKE A PATTERN CHANGE.  MAYBE NICE INTO WEEKEND...BUT MAY
BE GOING TO A SLIGHTLY WETTER PATTERN.

LOOKS A LITTLE LIKE FALL.  AWFUL DEEP VORTEX.

MISC.

NICE LOOKING HURRICANE OFF W COAST...WOW

MARTIN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 6:31 PM EDTSevere Thunderstorm WarningCTPHuntingdon64 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.