Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1994

Severe Thunderstorm Warning 5, NWS Philadelphia/Mount Holly

April 27, 1994Chester County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 27, 1994, 3:43 PM EDT for Chester County, Montgomery County, Pennsylvania. It was in force for 47 min.

The area

The counties it named.

The facts

Issued
Apr 27, 1994, 3:43 PM EDT (19:43 UTC)
Expired
Apr 27, 1994, 4:30 PM EDT
In force
47 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

Counties Chester County, PA, Montgomery County, PA

The nearest sounding before it

Atlantic City In, NJ (KACY), launched 12:00Z, 7.7 hours before the alert went out and 115 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 1994-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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 1994-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -206 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1588 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-206 m²/s²
0-3 km storm-relative helicity
-191 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 271944 RRA
SVRPHL
PAC029-091-272030-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHILADELPHIA/MOUNT HOLLY NJ
343 PM EDT WED APR 27 1994
 
THE NATIONAL WEATHER SERVICE IN PHILADELPHIA/MOUNT HOLLY HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  430 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST PENNSYLVANIA
 
   ...EASTERN CHESTER COUNTY...MONTGOMERY COUNTY
 
 
NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE THUNDERSTORM WAS
IN CENTRAL CHESTER COUNTY.  EARLIER THIS AFTERNOON THIS THUNDERSTORM
WAS RESPONSIBLE FOR BLOWING OFF SEVERAL BARN ROOFS IN YORK COUNTY.
 
MOVEMENT WAS EASTNORTHEAST AT 35 MILES AN HOUR.
 
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
Apr 27, 4:18 PM EDTSevere Thunderstorm WarningPHIBucks42 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.