Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 167, NWS State College, PA

September 11, 1997York County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Sep 11, 1997, 6:19 PM EDT for York County, Pennsylvania. It was in force for 56 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 11, 1997, 6:19 PM EDT (22:19 UTC)
Expired
Sep 11, 1997, 7:15 PM EDT
In force
56 min
Issued by
NWS State College, PA
Area
Whole counties

County York County, PA

What was reported inside it

TimeReportWhereRemark
Sep 11, 6:25 PM EDTThunderstorm Wind 50Menges Mill, PATrees and wires were blown down near Menges Mill in Jackson and Heidelburg townships.

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, 10.3 hours before the alert went out and 122 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 1997-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 16 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 12:00Z on 1997-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 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
16 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
550 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
111 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.

288 
WUUS01 KCTP 112223 RRA
SVRCTP
PAC133-112315-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
619 PM EDT THU SEP 11 1997
 
THE NATIONAL WEATHER SERVICE IN STATE COLLEGE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  715 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS......
 
IN  PENNSYLVANIA
 
   ...YORK COUNTY
 
AT 619 PM WEATHER SERVICE DOPPLER RADAR SHOWED A LINE OF SEVERE
THUNDERSTORMS ALONG THE WESTERN BORDER OF YORK COUNTY. THIS LINE WILL
MOVE NORTHEAST AND REACH THE CITY OF YORK BY 645 PM.
 
WHEN THUNDERSTORMS ARE OCCURRING...PEOPLE SHOULD MOVE INSIDE A
STRONG BUILDING.  DO NOT STAND BY WINDOWS.  DONT USE TELEPHONES
OR ELECTRICAL APPLIANCES UNLESS IN AN EMERGENCY UNTIL THE STORM
HAS PASSED.  MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS.
 
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 Sep 11, 2:20 PM EDT, 3 hours 59 minutes earlier.

Area forecast discussion, Sep 11, 2:20 PM EDT, 3 hours 59 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
215 PM EDT THU SEP 11 1997

THINGS VERY BUSY TODAY AT NWSO CTP TODAY...SO WILL KEEP THE
DISCUSSION SHORT.

ALL RIVER FLOOD AND FLASH FLOOD WARNINGS HAVE NOW EXPIRED IN THE
CWA.  RADAR SHOWS SCATTERED SHOWERS AND PATCHES OF RAIN AGAIN
BLOSSOMING ACROSS THE REGION.  ALTHOUGH THERE ARE STILL SOME HEAVY
RAIN PRODUCING CELLS IN THE AREA...THE SW FLOW NOW DOES NOT SUPPORT
TRAINING OF CELLS LIKE LAST NIGHT.

WEAK SURFACE FRONT IS LIMPING THROUGH THE STATE ATTM...WITH SURFACE
WINDS ACROSS CENTRAL AND WESTERN SECTIONS HAVING TURNED TO THE
SOUTHWEST.  VAD WINDS ALSO SHOWING THE VEERING TO THE SW.

MODELS INDICATE THAT DRIER AIR WILL SLOWLY MOVE INTO THE REGION
TONIGHT AS SHORTWAVE MOVE NORTHEAST OF THE AREA.  THEREFORE EXPECT
RAIN TO SLOWLY DIMINISH OVERNIGHT ACROSS CENTRAL SECTIONS.  STILL
CLOUDS...DRIZZLE AND SOME SHOWERS WILL BE PREVALENT LATER TONIGHT
INTO THE MORNING.

EARLY TOMORROW...NEXT VORT CENTER APPROACHES AS UPPER LOW CENTER
AND COLD CORE FINALLY PULLS ACROSS THE REGION BEFORE MOVING OUT.
MODELS ALSO SHOW WEAK SECONDARY FRONT CROSSING THE REGION AROUND
18Z.  THINK SHOWERS WILL BE POSSIBLE TOMORROW WITH THE COLD POCKET
ALOFT.  ALTHOUGH INSTABILITIES LIMITED...POSSIBLE THUNDERSTORMS
COULD BE EXPECTED ACROSS THE LOWER SUSQUEHANNA VALLEY AS CAPES
APPROACH 800.

JUNG

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 11:30 PM EDTFlash Flood WarningCTPCumberland, Franklin, Perry4 hr
Sep 11, 12:20 AM EDTFlash Flood WarningCTPAdams4 hr
Sep 11, 12:57 AM EDTFlash Flood WarningCTPSnyder, Union4 hr
Sep 11, 12:57 AM EDTFlash Flood WarningCTPJuniata4 hr
Sep 11, 3:27 AM EDTFlash Flood WarningCTPAdams, Cumberland, Perry5 hr
Sep 11, 4:00 AM EDTFlash Flood WarningCTPLancaster4 hr
Sep 11, 4:57 AM EDTFlash Flood WarningCTPJuniata, Snyder3 hr
Sep 11, 7:46 AM EDTFlash Flood WarningCTPCumberland, Perry3 hr
Sep 11, 10:41 AM EDTFlash Flood WarningCTPCumberland, Perry3 hr

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.