Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1993
Severe Thunderstorm Warning 19, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 20, 1993, 8:08 PM EDT for Chester County, Pennsylvania. It was in force for 52 min.
The area
The counties it named.
The facts
- Issued
- Jun 20, 1993, 8:08 PM EDT (00:08 UTC)
- Expired
- Jun 20, 1993, 9:00 PM EDT
- In force
- 52 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Whole counties
County Chester County, PA
The nearest sounding before it
Atlantic City In, NJ (KACY), launched 00:00Z, 0.1 hours before the alert went out and 122 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.
- Mixed-layer CAPE
- 335 J/kg
- Mixed-layer CIN
- -112 J/kg
- Mixed-layer LCL
- 1172 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 53 m²/s²
- 0-3 km storm-relative helicity
- 82 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS1 KPHL 210008 RRA SVRPHL PAC029-210115- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE PHILADELPHIA PA 808 PM EDT SUN JUN 20 1993 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 ...CHESTER COUNTY NATIONAL WEATHER SERVICE RADARS INDICATE A SEVERE THUNDERSTORM WITH STRONG GUSTY WINDS AND HAIL TO 1 INCH IN DIAMETER NEAR PARKESBURG IN CHESTER COUNTY. THIS STORM IS MOVING TO THE EAST AT 25 TO 30 MPH AND WILL EFFECT CHESTER COUNTY UNTIL 9 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.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, Jun 20, 7:31 PM EDT, 37 minutes before
DEZ003-002-210230- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WILMINGTON DE 729 PM EDT SUN JUN 20 1993 ...THUNDERSTORMS MOVING TOWARD NORTHERN DELAWARE... AT 729 PM THIS EVENING WEATHER SERVICE RADAR SHOWED A LINE OF THUNDERSTORMS FROM LANCASTER PENNSYLVANIA SOUTHWARD TO JUST EAST OF BALTIMORE MARYLAND. THESE THUNDERSTORMS WERE MOVING TO THE EAST AT NEAR 25 MPH. THESE STORMS HAVE BEEN PRODUCING VERY HEAVY RAIN...STRONG GUSTY WINDS...DEADLY LIGHTNING AND SOME HAIL. THESE STORMS WILL MOVE INTO NORTHERN KENT COUNTY AND NEW CASTLE JUST AFTER 800 PM EDT THIS EVENING. PERSONS SHOULD KEEP AN EYE OUT FOR THREATENING WEATHER CONDITIONS. IF THREATENING WEATHER APPROACHES SEEK SAFE SHELTER IMMEDIATELY INDOOR...STAY AWAY FROM WINDOWS AND AVOID USING ELECTRICAL APPLIANCES INCLUDING THE TELEPHONE. REMEMBER...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR ALL OF DELAWARE UNTIL 1100 PM EDT TONIGHT. VAUGHAN
Special weather statement, Jun 20, 7:34 PM EDT, 34 minutes before
DEZ003-002-210230- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WILMINGTON DE 729 PM EDT SUN JUN 20 1993 ...THUNDERSTORMS MOVING TOWARD NORTHERN DELAWARE... AT 729 PM THIS EVENING WEATHER SERVICE RADAR SHOWED A LINE OF THUNDERSTORMS FROM LANCASTER PENNSYLVANIA SOUTHWARD TO JUST EAST OF BALTIMORE MARYLAND. THESE THUNDERSTORMS WERE MOVING TO THE EAST AT NEAR 25 MPH. THESE STORMS HAVE BEEN PRODUCING VERY HEAVY RAIN...STRONG GUSTY WINDS...DEADLY LIGHTNING AND SOME HAIL. THESE STORMS WILL MOVE INTO NORTHERN KENT COUNTY AND NEW CASTLE JUST AFTER 800 PM EDT THIS EVENING. PERSONS SHOULD KEEP AN EYE OUT FOR THREATENING WEATHER CONDITIONS. IF THREATENING WEATHER APPROACHES SEEK SAFE *SHELTER IMMEDIATELY INDOORS...STAY AWAY FROM WINDOWS AND AVOID USING ELECTRICAL APPLIANCES INCLUDING THE TELEPHONE. REMEMBER...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR ALL OF DELAWARE UNTIL 1100 PM EDT TONIGHT. VAUGHAN
Special weather statement, Jun 20, 7:35 PM EDT, 33 minutes before
DEZ003-002-210230- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WILMINGTON DE 729 PM EDT SUN JUN 20 1993 ...THUNDERSTORMS MOVING TOWARD NORTHERN DELAWARE... AT 729 PM THIS EVENING WEATHER SERVICE RADAR SHOWED A LINE OF THUNDERSTORMS FROM LANCASTER PENNSYLVANIA SOUTHWARD TO JUST EAST OF BALTIMORE MARYLAND. THESE THUNDERSTORMS WERE MOVING TO THE EAST AT NEAR 25 MPH. THESE STORMS HAVE BEEN PRODUCING VERY HEAVY RAIN...STRONG GUSTY WINDS...DEADLY LIGHTNING AND SOME HAIL. THESE STORMS WILL MOVE INTO NORTHERN KENT COUNTY AND NEW CASTLE JUST AFTER 800 PM EDT THIS EVENING. PERSONS SHOULD KEEP AN EYE OUT FOR THREATENING WEATHER CONDITIONS. IF THREATENING WEATHER APPROACHES SEEK SAFE .SHELTER IMMEDIATELY INDOORS...STAY AWAY FROM WINDOWS AND AVOID USING ELECTRICAL APPLIANCES INCLUDING THE TELEPHONE. REMEMBER...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR ALL OF DELAWARE UNTIL 1100 PM EDT TONIGHT. VAUGHAN
Special weather statement, Jun 20, 7:53 PM EDT, 15 minutes before
NJZ003-004-006-202330 SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE ATLANTIC CITY NJ 730 PM EDT SUN JUN 20 1993 ...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 11 PM IN CUMBERLAND COUNTY... AT 730 PM...WEATHER SERVICE RADAR DETECTED A LARGE AREA OF STRONG THUNDERSTORMS COVERING EASTERN PENNSYLVANIA...EXTREME WESTERN NEW JERSEY AND NORTHEAST MARYLAND. THE THUNDERSTORMS STRETCHED FROM SULLIVAN COUNTY NEW YORK THROUGH NORTHAMPTON PENNSYLVANIA...POTTVILLE...LANCASTER... YORK...HARFORD COUNTY MARYLAND...TO LOUDON COUNTY VIRGINIA. THE INTENSITY OF THE THUNDERSTORMS HAS INCREASED OVER THE PAST HOUR AND MOVEMENT WAS EAST AT 30 MILES AN HOUR. SURFACE REPORTS INDICATE FREQUENT THUNDER AND LIGHTNING FROM HARRISBURG TO NORTHEAST PHILADELPHIA WITH LIGHTNING VISIBLE AT MCQUIRE AIR FORCE BASE. AN AMATEUR RADIO OPERATOR REPORTED AN ANTENNA BLOWN DOWN IN LANCASTER COUNTY PENNSYLVANIA BY GUSTY WINDS. REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS EXIST FOR THE DEVELOPMENT OF SEVERE THUNDERSTORMS. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. GERAPETRITIS
Special weather statement, Jun 20, 8:00 PM EDT, 8 minutes before
PAZ011-016-210200- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ALLENTOWN PA 800 PM EDT SUN JUN 20 1993 ...SEVERE THUNDERSTORM WATCH FOR ALL OF EAST CENTRAL PENNSYLVANIA AND THE POCONOS UNTIL 10PM THIS EVENING... AT 800 PM RADAR INDICATED AN AREA OF THUNDERSTORMS NORTH OF ALLENTOWN EXTENDING EAST INTO SUSSEX COUNTY NEW JERSEY. ANOTHER...LARGER AREA OF THUNDERSTORMS COVERED MUCH OF SCHUYLKILL...BERKS AND WESTERN CARBON COUNTIES. THESE THUNDERSTORMS ARE PRODUCING HEAVY DOWNPOURS...GUSTY WINDS AND DANGEROUS LIGHTNING BUT NO REPORTS OF SEVERE WEATHER HAVE BEEN REPORTED. IN 30 MINUTE PERIOD .85" OF RAIN WAS RECORDED AT CAMELBACK MT. IN MONROE COUNTY. MOVEMENT OF THESE THUNDERSTORMS HAS BEEN TO THE EAST AT AROUND 25 MPH. CONDITIONS REMAIN FAVORABLE FOR THE FORMATION OF SEVERE THUNDERSTORMS. IF THREATENING WEATHER APPROACHES...SEEK SHELTER INSIDE A STRONG BUILDING OR HOUSE. HEAVY DOWNPOURS ACCOMPANYING THUNDERSTORMS MAY CAUSE FLOODING STAY TUNED TO NOAA WEATHER RADIO OR LOCAL TELEVISION AND RADIO FOR ADDITIONAL STATEMENTS OR POSSIBLE WARNINGS. LOEPER
Special weather statement, Jun 20, 8:02 PM EDT, 6 minutes before
PAZ011-016-210200- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ALLENTOWN PA 800 PM EDT SUN JUN 20 1993 ...SEVERE THUNDERSTORM WATCH FOR ALL OF EAST CENTRAL PENNSYLVANIA AND THE POCONOS UNTIL 10PM THIS EVENING... AT 800 PM RADAR INDICATED AN AREA OF THUNDERSTORMS NORTH OF ALLENTOWN EXTENDING EAST INTO SUSSEX COUNTY NEW JERSEY. ANOTHER...LARGER AREA OF THUNDERSTORMS COVERED MUCH OF SCHUYLKILL...BERKS AND WESTERN CARBON COUNTIES. THESE THUNDERSTORMS ARE PRODUCING HEAVY DOWNPOURS...GUSTY WINDS AND DANGEROUS LIGHTNING BUT NO REPORTS OF SEVERE WEATHER HAVE BEEN REPORTED. IN 30 MINUTE PERIOD .85" OF RAIN WAS RECORDED AT CAMELBACK MT. IN MONROE COUNTY. MOVEMENT OF THESE THUNDERSTORMS HAS BEEN TO THE EAST AT AROUND 25 MPH. CONDITIONS REMAIN FAVORABLE FOR THE FORMATION OF SEVERE THUNDERSTORMS. IF THREATENING WEATHER APPROACHES...SEEK SHELTER INSIDE A STRONG BUILDING OR HOUSE. HEAVY DOWNPOURS ACCOMPANYING THUNDERSTORMS MAY CAUSE FLOODING STAY TUNED TO NOAA WEATHER RADIO OR LOCAL TELEVISION AND RADIO FOR ADDITIONAL STATEMENTS OR POSSIBLE WARNINGS. LOEPER
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 21, 5:41 PM EDT | Severe Thunderstorm Warning | PHI | Montgomery | 64 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 1993Every severe thunderstorm warning in 1993
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.