Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 21, NWS Pittsburgh, PA

April 8, 1998Mercer County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Apr 8, 1998, 4:51 PM EDT for Mercer County, Pennsylvania. It was in force for 54 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 8, 1998, 4:51 PM EDT (20:51 UTC)
Expired
Apr 8, 1998, 5:45 PM EDT
In force
54 min
Issued by
NWS Pittsburgh, PA
Area
Whole counties

County Mercer County, PA

The radar

The Pittsburgh radar (KPBZ), 86 km from the middle of the area, began a volume at 20:52 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.

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 8.9 hours before the alert went out and 100 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 1998-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 19 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Pittsburgh, PA at 12:00Z on 1998-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 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
19 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
824 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
216 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

369 
WUUS1 KPIT 082055 RRA
SVRPIT
PAC085-082145-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PITTSBURGH PA
451 PM EDT WED APR 8 1998
 
THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  545 PM EDT
FOR THE FOLLOWING LOCATION...
 
IN NORTHWEST PENNSYLVANIA
 
   ...MERCER COUNTY
 
AT 555 PM EDT NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE STORM
AROUND 8 MILES NORTH OF SHARON...MOVING EAST AROUND 25 MPH. THIS STORM
WILL LIKELY PRODUCE LARGE HAIL AND MAY ALSO PRODUCE DAMAGING WIND GUSTS
NEAR 60 MPH AS IT PASSES NEAR TRANSFER AND FREDONIA.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND OVER 55 MPH...DESTRUCTIVE
HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR YOUR PROTECTION
MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR BUILDING.  HEAVY
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER
COVERS THE ROAD.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 8, 4:14 PM EDTSevere Thunderstorm WarningPBZWashington61 min
Apr 8, 4:23 PM EDTSevere Thunderstorm WarningPBZJefferson52 min
Apr 8, 4:28 PM EDTSevere Thunderstorm WarningPBZBeaver62 min
Apr 8, 4:45 PM EDTSevere Thunderstorm WarningPBZAllegheny60 min
Apr 8, 5:05 PM EDTSevere Thunderstorm WarningPBZWashington40 min
Apr 8, 5:10 PM EDTSevere Thunderstorm WarningPBZWestmoreland50 min
Apr 8, 5:16 PM EDTSevere Thunderstorm WarningPBZWestmoreland44 min
Apr 8, 5:28 PM EDTSevere Thunderstorm WarningPBZArmstrong47 min
Apr 8, 5:37 PM EDTSevere Thunderstorm WarningPBZIndiana53 min
Apr 8, 5:50 PM EDTSevere Thunderstorm WarningPBZWestmoreland40 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.