Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 169, NWS State College, PA

July 21, 1998Fulton County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 21, 1998, 4:53 PM EDT for Fulton County, Pennsylvania. It was in force for 32 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
Jul 21, 1998, 4:53 PM EDT (20:53 UTC)
Expired
Jul 21, 1998, 5:25 PM EDT
In force
32 min
Issued by
NWS State College, PA
Area
Whole counties

County Fulton County, PA

What was reported inside it

TimeReportWhereRemark
Jul 21, 5:19 PM EDTThunderstorm Wind 51Amaranth, PAA tree was blown onto Interstate 70.

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, 8.9 hours before the alert went out and 177 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 1998-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1313 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 1998-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 146 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
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, 20 hours 3 minutes earlier.

Area forecast discussion, Jul 20, 8:50 PM EDT, 20 hours 3 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 53 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, 2 hours 28 minutes before
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Special weather statement, Jul 21, 2:25 PM EDT, 2 hours 28 minutes before
<!doctype html>
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Special weather statement, Jul 21, 3:00 PM EDT, 1 hour 53 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.

IssuedProductOfficeCountiesLasted
Jul 21, 9:56 AM EDTSevere Thunderstorm WarningCTPPotter64 min
Jul 21, 10:48 AM EDTSevere Thunderstorm WarningCTPTioga62 min
Jul 21, 11:01 AM EDTTornado WarningCTPTioga64 min
Jul 21, 11:43 AM EDTSevere Thunderstorm WarningCTPLycoming, Sullivan67 min
Jul 21, 11:43 AM EDTSevere Thunderstorm WarningCTPLycoming, Sullivan62 min
Jul 21, 12:42 PM EDTSevere Thunderstorm WarningCTPColumbia63 min
Jul 21, 1:17 PM EDTTornado WarningCTPColumbia63 min
Jul 21, 1:24 PM EDTTornado WarningCTPColumbia56 min
Jul 21, 4:11 PM EDTSevere Thunderstorm WarningCTPSomerset74 min
Jul 21, 4:36 PM EDTSevere Thunderstorm WarningCTPBedford59 min
Jul 21, 4:55 PM EDTSevere Thunderstorm WarningCTPFulton30 min
Jul 21, 5:21 PM EDTSevere Thunderstorm WarningCTPLebanon19 min
Jul 21, 6:11 PM EDTSevere Thunderstorm WarningCTPLancaster34 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1998Every 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.