Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1992

Severe Thunderstorm Warning 36, NWS Philadelphia/Mount Holly

July 17, 1992Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 1992, 8:34 PM EDT for Delaware County, Pennsylvania. It was in force for 41 min.

The area

The counties it named.

The facts

Issued
Jul 17, 1992, 8:34 PM EDT (00:34 UTC)
Expired
Jul 17, 1992, 9:15 PM EDT
In force
41 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 00:00Z, 0.6 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 00:00Z on 1992-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1825 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 00:00Z on 1992-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.1939Sfc1 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
1825 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
887 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
137 m²/s²
Significant tornado parameter
0.8
Supercell composite
4.9

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPHL 180036
SVRPHL
PAC045-180115-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHILADELPHIA PA
834 PM EDT FRI JUL 17 1992
 
THE NATIONAL WEATHER SERVICE IN PHILADELPHIA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  915 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHEAST PENNSYLVANIA
 
   ...DELAWARE COUNTY
 
AT 830 PM...NATIONAL WEATHER SERVICE RADAR INDICATED A THUNDERSTORM IN
EASTERN CHESTER COUNTY. THIS THUNDERSTORM IS MOVING TO THE EAST AT
AROUND 25 MPH...AND IT WAS ACCOMPANIED BY STRONG WIND GUSTS AS IT MOVED
ACROSS CHESTER COUNTY DURING THE PAST HOUR. THE STORM IS EXPECTED TO
MOVE ACROSS DELAWARE COUNTY BETWEEN NOW AND 915 PM.
 
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.
 
IOVINO

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 8:41 PM EDTSevere Thunderstorm WarningPHIChester64 min
Jul 17, 9:03 PM EDTSevere Thunderstorm WarningPHIMontgomery, Philadelphia42 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1992Every severe thunderstorm warning in 1992

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.