Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1996

Severe Thunderstorm Warning 112, NWS Philadelphia/Mount Holly

September 8, 1996Bucks County, Delaware County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 8, 1996, 6:16 PM EDT for Bucks County, Delaware County, Philadelphia County, Pennsylvania. It was in force for 44 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
Sep 8, 1996, 6:16 PM EDT (22:16 UTC)
Expired
Sep 8, 1996, 7:00 PM EDT
In force
44 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

Counties Bucks County, PA, Delaware County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 70 km from the middle of the area, began a volume at 22:16 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 8, 6:30 PM EDTThunderstorm WindNortheast, PA
Sep 8, 6:30 PM EDTThunderstorm WindBristol, 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 nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.3 hours before the alert went out and 217 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 12:00Z on 1996-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 153 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, Brookhaven, NY at 12:00Z on 1996-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 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
153 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
566 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
196 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPHL 082217
SVRPHL
PAC017-045-101-082300-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHILADELPHIA/MOUNT HOLLY NJ
616 PM EDT SUN SEP 8 1996
 
THE NATIONAL WEATHER SERVICE IN PHILADELPHIA/MOUNT HOLLY HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  700 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN  PENNSYLVANIA
 
   ...SOUTHERN BUCKS COUNTY...DELAWARE COUNTY
   ...PHILADELPHIA COUNTY
 
AT 615 PM...NATIONAL WEATHER SERVICE RADAR SHOWED SEVERE THUNDERSTORMS
MOVING ACROSS DELAWARE...PHILADELPHIA AND SOUTHERN BUCKS COUNTIES. THESE
THUNDERSTORMS WERE MOVING EAST AT 20 MPH.
 
THIS IS A DANGEROUS STORM.  PREPARE FOR STRONG DAMAGING WINDS...
LARGE HAIL...HEAVY RAINS AND DEADLY LIGHTNING.  SHOULD THE STORM
APPROACH MOVE INSIDE QUICKLY. DO NOT STAND NEAR WINDOWS.  MOBILE
HOMES ARE MOST VULNERABLE TO HIGH WINDS AND SHOULD BE AVOIDED.
 
HEAVY RAINS WITH THIS THUNDERSTORM MAY CAUSE FLOODING OF SMALL
STREAMS AND UNDERPASSES VERY QUICKLY.  DO NOT DRIVE YOUR CAR INTO
AREAS WHERE THE WATER COVERS THE ROADWAY.  THE WATER MAY BE DEEPER
THAN YOU THINK.  IF CAUGHT IN RISING WATERS...ABANDON YOUR CAR
QUICKLY.  MOVE TO HIGHER GROUND.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 8, 6:23 PM EDTFlash Flood WarningPHIBucks, Philadelphia2 hr
Sep 8, 6:29 PM EDTFlash Flood WarningPHIMontgomery2 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1996Every severe thunderstorm warning in 1996

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.