Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 42, NWS Philadelphia/Mount Holly

May 31, 1998Bucks County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 31, 1998, 10:21 PM EDT for Bucks County, Montgomery County, Pennsylvania. It was in force for 49 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
May 31, 1998, 10:21 PM EDT (02:21 UTC)
Expired
May 31, 1998, 11:10 PM EDT
In force
49 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

Counties Bucks County, PA, Montgomery County, PA

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 31, 10:00 PM EDTTornado WatchSPC6 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 2.4 hours before the alert went out and 211 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, Brookhaven, NY at 00:00Z on 1998-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 151 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, Brookhaven, NY at 00:00Z on 1998-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 233 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
151 J/kg
Mixed-layer CIN
-348 J/kg
Mixed-layer LCL
1224 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
233 m²/s²
0-3 km storm-relative helicity
319 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.

490 
WUUS1 KPHL 010223 RRA
SVRPHL
PAC017-091-010310-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1021 PM EDT SUN MAY 31 1998

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  MONTGOMERY COUNTY IN PENNSYLVANIA
  CENTRAL AND SOUTHERN BUCKS COUNTY IN PENNSYLVANIA

* UNTIL 1110 PM EDT

* AT 1019 PM EDT... NATIONAL WEATHER SERVICE DOPPLER RADAR
  INDICATED A SEVERE THUNDERSTORM IN THE VICINITY OF GWYNEDD VALLEY
  MOVING EAST AT 50 MPH.

* THE SEVERE THUNDERSTORM IS EXPECTED TO BE NEAR...
  PENNDEL AT 1024 PM EDT
  NEWTOWN AT 1025 PM EDT
  HULMEVILLE AT 1026 PM EDT
  NEW HOPE AT 1026 PM EDT
  BRISTOL AT 1027 PM EDT
  WASHINGTON CROSSING AT 1030 PM EDT
  YARDLEY AT 1031 PM EDT
  TULLYTOWN AT 1031 PM EDT
  MORRISVILLE AT 1033 PM EDT

A TORNADO WATCH REMAINS IN EFFECT FOR THE AREA. SEVERE
THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH
LITTLE OR NO ADVANCE WARNING.

THIS IS A DANGEROUS STORM. MOVE INSIDE A STRONG BUILDING AND DO
NOT STAND NEAR WINDOWS. FOR YOUR PROTECTION MOVE TO AN INTERIOR
ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS.

FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER
RADIO...YOUR LOCAL RADIO OR TELEVISION STATIONS...OR YOUR CABLE
TELEVISION OUTLET.

KRAUS/DELISI

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 31, 8:11 PM EDTSevere Thunderstorm WarningPHIBerks64 min
May 31, 8:37 PM EDTTornado WarningPHIBerks33 min
May 31, 9:07 PM EDTTornado WarningPHIBerks, Lehigh48 min
May 31, 9:14 PM EDTSevere Thunderstorm WarningPHIBerks46 min
May 31, 9:39 PM EDTTornado WarningPHIBerks, Chester36 min
May 31, 9:43 PM EDTTornado WarningPHIBucks32 min
May 31, 10:01 PM EDTTornado WarningPHIMonroe34 min
May 31, 11:01 PM EDTSevere Thunderstorm WarningPHINorthampton34 min
Jun 1, 12:17 AM EDTSevere Thunderstorm WarningPHIBerks48 min
Jun 1, 12:40 AM EDTSevere Thunderstorm WarningPHIChester50 min
Jun 1, 12:54 AM EDTSevere Thunderstorm WarningPHIBucks31 min
Jun 1, 1:00 AM EDTSevere Thunderstorm WarningPHIDelaware50 min
Jun 1, 1:15 AM EDTSevere Thunderstorm WarningPHIPhiladelphia35 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.