Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1994

Severe Thunderstorm Warning 29, NWS Philadelphia/Mount Holly

June 6, 1994Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 6, 1994, 6:15 PM EDT for Delaware County, Pennsylvania. It was in force for 45 min.

The area

The counties it named.

The facts

Issued
Jun 6, 1994, 6:15 PM EDT (22:15 UTC)
Expired
Jun 6, 1994, 7:00 PM EDT
In force
45 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

County Delaware County, PA

The nearest sounding before it

Atlantic City In, NJ (KACY), launched 12:00Z, 10.3 hours before the alert went out and 93 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, Atlantic City In, NJ at 12:00Z on 1994-06-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 319 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, Atlantic City In, NJ at 12:00Z on 1994-06-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 103 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
319 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
621 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
103 m²/s²
0-3 km storm-relative helicity
116 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 062219 COR
SVRPHL
PAC045-062300-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING...CORRECTED
NATIONAL WEATHER SERVICE PHILADELPHIA/MOUNT HOLLY NJ
615 PM EDT MON JUN 6 1994

THE NATIONAL WEATHER SERVICE IN PHILADELPHIA/MOUNT HOLLY HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  700 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN SOUTHEAST PENNSYLVANIA

   ...NORTHERN DELAWARE COUNTY

AT 610 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE
THUNDERSTORM MOVING OUT OF NORTHERN CHESTER COUNTY INTO NORTHERN DELAWARE
COUNTY. THE THUNDERSTORM WAS MOVING TOWARD THE EAST-SOUTHEAST AT 10 TO
15 MPH.

THIS IS A DANGEROUS STORM.  IF YOU ARE IN THE WARNED AREA...PREPARE
FOR STRONG DAMAGING WINDS...LARGE HAIL...VERY HEAVY RAIN AND DEADLY
LIGHTNING.  SHOULD THE STORM APPROACH YOU...SEEK IMMEDIATE SHELTER
INDOORS...BUT DO NOT STAND NEAR WINDOWS.  MOBILE HOMES ARE MOST
VULNERABLE TO HIGH WINDS AND SHOULD BE AVOIDED.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 6, 5:20 PM EDTSevere Thunderstorm WarningPHIChester55 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1994Every severe thunderstorm warning in 1994

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.