Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 154, NWS Philadelphia/Mount Holly

September 7, 1998Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 7, 1998, 12:30 PM EDT for Berks County, Pennsylvania. It was in force for 60 min. 3 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
Sep 7, 1998, 12:30 PM EDT (16:30 UTC)
Expired
Sep 7, 1998, 1:30 PM EDT
In force
60 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 139 km from the middle of the area, began a volume at 16:31 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

TimeReportWhereRemark
Sep 7, 12:40 PM EDTHail 0.75Robesonia, PA
Sep 7, 12:45 PM EDTThunderstorm Wind 60Central Portion, PA
Sep 7, 1:00 PM EDTThunderstorm Wind 55Bechtelsville, PA

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 watch it was issued in

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

IssuedProductOfficeLasted
Sep 7, 10:45 AM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 4.5 hours before the alert went out and 206 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 1998-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 114 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, Washington/Dulle, VA at 12:00Z on 1998-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
114 J/kg
Mixed-layer CIN
-252 J/kg
Mixed-layer LCL
2079 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
96 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.

000 
TTAA00 KPHL 071630 RRA
SVRPHL
PAC011-071730-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1230 PM EDT MON SEP 7 1998

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BERKS COUNTY IN PENNSYLVANIA

* UNTIL 130 PM EDT

* AT 1225 PM EDT... A SEVERE THUNDERSTORM WAS INDICATED 14 MILES
  SOUTHWEST OF FRYSTOWN... BY NATIONAL WEATHER SERVICE DOPPLER
  RADAR... MOVING EAST 45 MPH.

* THE SEVERE THUNDERSTORM IS EXPECTED TO BE NEAR...
  FRYSTOWN AT 1235 PM EDT
  MT AETNA AT 1240 PM EDT
  WOMELSDORF AT 1245 PM EDT
  READING AT 125 PM EDT

THESE STORMS HAVE A HISTORY OF LARGE HAIL AND DAMAGING WINDS.
WINDS GUSTED TO NEAR 60 MPH IN HARRISBURG PA.

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 INFORMATIOND...PLEASE TUNE TO NOAA WEATHER
RADIO...YOUR LOCAL RADIO OR TELEVISION STATIONS...OR YOUR CABLE
TELEVISION OUTLET.

NC/AMC

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 12:22 PM EDTSevere Thunderstorm WarningPHICarbon53 min
Sep 7, 12:35 PM EDTSevere Thunderstorm WarningPHIMonroe60 min
Sep 7, 12:46 PM EDTSevere Thunderstorm WarningPHILehigh, Northampton59 min
Sep 7, 1:04 PM EDTSevere Thunderstorm WarningPHIChester, Montgomery61 min
Sep 7, 1:19 PM EDTSevere Thunderstorm WarningPHIBucks61 min
Sep 7, 1:39 PM EDTSevere Thunderstorm WarningPHIDelaware, Philadelphia51 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; radar from the NEXRAD Level II archive.