Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 167, NWS State College, PA

July 21, 1998Somerset County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 21, 1998, 4:11 PM EDT for Somerset County, Pennsylvania. It was in force for 74 min. 2 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 21, 1998, 4:11 PM EDT (20:11 UTC)
Expired: Jul 21, 1998, 5:25 PM EDT
In force: 74 min
Issued by: NWS State College, PA
Area: Whole counties

County Somerset County, PA

The radar

The Pittsburgh radar (KPBZ), 119 km from the middle of the area, began a volume at 20:14 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

Time	Report	Where	Remark
Jul 21, 4:30 PM EDT	Thunderstorm Wind 51	Somerset, PA
Jul 21, 4:35 PM EDT	Thunderstorm Wind 51	Shanksville, PA	Trees were down in Somerset and other spots in the county. A tree also fell on a home in Shanksville.

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

Pittsburgh, PA (KPIT), launched 12:00Z, 8.2 hours before the alert went out and 103 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1313 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 676 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 146 m²/s²
0-3 km storm-relative helicity: 225 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 5.1

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.

NWS State College, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 20, 8:50 PM EDT, 19 hours 21 minutes earlier.

Area forecast discussion, Jul 20, 8:50 PM EDT, 19 hours 21 minutes before

CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
850 PM EDT MON JUL 20 1998

...ZONES WL BE AVBL TO PIT/PHL VIA ADMCTP AROUND 920 PM...

...DISCUSSION...

FAIRLY CLEAR AND QUIET EARLY EVENING ACROSS CENTRAL AND WESTERN PA
IS NO INDICATION OF WHAT WILL ARRIVE IN JUST AN HOUR ACROSS THE
NORTHWEST COUNTIES...AND PROBABLY THROUGH THE REMAINDER OF THE
NORTHWEST OF ROUTE 220 (I.E. KAOO TO KIPT LINE) BY 04-05Z. SPC JUST
SENT PRELIM MESSAGE FOR SVR TSRA WATCH TIL 07Z.

DCURRENT LARGE SCALE BOW ECHO MOVING INTO NW PA WILL MAINTAIN ITS
BEST STRENGTH ON THE SRN FLANK AS IT MOVES/DEVELOPS SE ALONG THE
BEST MESOSCALE INSTABILITY/MOIST CONVERGENCE AXIS. NEW DEVELOPMENT
EXPECTED WITH A WEAK SHORT WAVE/AREA OF H250 DIVERGENCE LATER
TONIGHT MAY SHOW PREFERENCE FOR FORMING ACROSS SWRN PA AND THE
LAUREL HIGHLANDS ALONG THE OUTFLOW BOUNDARY FROM THE CURRENT SQUALL
LINE.

DIFFICULT QPF FORECAST WITH EXTREME RANGE IN PRECIP BETWEEN
GRIDPOINTS ONLY 100 MI APART. STRONG BELT OF WESTERLIES ALOFT WILL
GRADUALLY SETTLE SOUTH OVER THE GREAT LAKES AND U.S/QUEBEC BORDER
DURING THE NEXT 48 HOURS IN CONJUNCTION WITH SLOWLY FALLING HEIGHTS.

BAND OF STRONG LLVL CONVERGENCE/VVEL WILL SET UP ALONG A QUASI STNRY
FRONT...WHICH WILL EVENTUALLY BECOME STRUNG OUT ON A KORD TO KCLE
AND KROC LINE BY EARLY WED AFTERNOON.

QPF AMOUNTS OVER 2.0 PROJECTED BY THE ETA ACROSS THE NW COUNTIES
OF PA WITH GENERALLY .25 TO .50 SE OF KAOO AND KIPT.

THUS...I DONT HAVE A HIGH DEGREE OF CONFIDENCE IN ETA QPF...WHICH
MAY ACTUALLY BE THE HIGHEST OVER THE SW AND SCENT COUNTIES DURING
THE NEXT 18 TO 24 HOURS.

WILL RE-ISSUE AN SPS FOR POTENTIAL HEAVY RAINS AND KEEP A CLOSE EYE
ON MVMT/REDEVELOPMENT OF TSRA OVER OHIO FOR A POSSIBLE FLASH FLOOD
WATCH.

MBE (MESO BETA ELEMENT) VECTORS VIA ETA HOURLY PROFILE DATA ARE WEAK
FROM THE SSE SUGGESTING A STRONG TENDENCY FOR TRAINING ECHOES
OVERNIGHT.

WILL ADJUST WORDING OF PRECIP OVERNIGHT AND UP POPS IN ALL AREAS OF
THE CENT AND WEST.

.CTP...SEVERE THUNDERSTORM WATCH TIL 07Z FOR
       PAZ004>006-010-011-017>019-024>026-033-034

LAMBERT

In the hours before

Special weather statement, Jul 21, 11:00 AM EDT, 5 hours 11 minutes before

PAZ004>006-010>012-017-018-024>028-033>037-041-042-045>046-049>053
-211505-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
11 AM EDT TUE JUL 21 1998

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING OVER NORTHERN PENNSYLVANIA...

A WARM FRONT WILL USHER INTO THE REGION...VERY WARM...MOIST AND
UNSTABLE AIR. THIS WILL SET THE STAGE FOR POSSIBLE SEVERE
THUNDERSTORMS THIS AFTERNOON AND EVENING.

THE MAIN THREAT FROM THE THUNDERSTORMS WILL BE DAMAGING STRAIGHT LINE
WINDS AND LOCALLY HEAVY RAIN.

SKYWARN ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON OR EVENING.

STAY TUNED TO NOAA WEATHER RADIO...OR YOUR FAVORITE LOCAL RADIO OR
TELEVISION STATION FOR THE LATEST FORECASTS...STATEMENTS AND
POSSIBLE WARNINGS.

LA CORTE

Special weather statement, Jul 21, 2:25 PM EDT, 1 hour 46 minutes before

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Special weather statement, Jul 21, 2:25 PM EDT, 1 hour 46 minutes before

<!doctype html>
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Special weather statement, Jul 21, 3:00 PM EDT, 1 hour 11 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 9:56 AM EDT	Severe Thunderstorm Warning	CTP	Potter	64 min
Jul 21, 10:48 AM EDT	Severe Thunderstorm Warning	CTP	Tioga	62 min
Jul 21, 11:01 AM EDT	Tornado Warning	CTP	Tioga	64 min
Jul 21, 11:43 AM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan	67 min
Jul 21, 11:43 AM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan	62 min
Jul 21, 12:42 PM EDT	Severe Thunderstorm Warning	CTP	Columbia	63 min
Jul 21, 1:17 PM EDT	Tornado Warning	CTP	Columbia	63 min
Jul 21, 1:24 PM EDT	Tornado Warning	CTP	Columbia	56 min
Jul 21, 4:36 PM EDT	Severe Thunderstorm Warning	CTP	Bedford	59 min
Jul 21, 4:53 PM EDT	Severe Thunderstorm Warning	CTP	Fulton	32 min
Jul 21, 4:55 PM EDT	Severe Thunderstorm Warning	CTP	Fulton	30 min
Jul 21, 5:21 PM EDT	Severe Thunderstorm Warning	CTP	Lebanon	19 min
Jul 21, 6:11 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster	34 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1998 Every severe thunderstorm warning in 1998

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.