Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 6, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 6, 1991, 6:48 PM EDT for Philadelphia County, Pennsylvania. It was in force for 27 min.
The area
The counties it named.
The facts
- Issued
- May 6, 1991, 6:48 PM EDT (22:48 UTC)
- Expired
- May 6, 1991, 7:15 PM EDT
- In force
- 27 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Whole counties
County Philadelphia County, PA
The nearest sounding before it
Atlantic City In, NJ (KACY), launched 12:00Z, 10.8 hours before the alert went out and 82 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 574 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 224 m²/s²
- 0-3 km storm-relative helicity
- 288 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KPHL 062250 SVRPHL PAC101-062315- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE PHILADELPHIA PA 648 PM EDT MON MAY 6 1991 THE NATIONAL WEATHER SERVICE IN PHILADELPHIA HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 715 PM EDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN SOUTHEAST PENNSYLVANIA ...PHILADELPHIA COUNTY AT 645 PM WEATHER SERVICE RADAR SHOWED THUNDERSTORMS MOVING THROUGH PHILADELPHIA COUNTY. SOME OF THESE THUNDERSTORMS MAY BE ACCOMPANIED BY WIND GUSTS TO OVER 60 MPH. WIND GUSTS OF 54 MPH WERE REPORTED WHEN THE THUNDERSTORMS PASSED OVER INTERNATIONAL AIRPORT. A TORNADO WATCH CONTINUES FOR SOUTHEASTERN PENNSYLVANIA AND SOUTHERN NEW JERSEY UNTIL 1000 PM EDT. REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCED WARNING.
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, May 6, 5:23 PM EDT, 1 hour 25 minutes before
PAZ007>012-016-NJZ002>004-006-062300- SEVERE WEATHER STATEMENT - NATIONAL WEATHER SERVICE PHILADELPHIA PA 530 PM EDT MON MAY 6 1991 ...TORNADO WATCH IN EFFECT FOR SOUTHEAST PENNSYLVANIA AND MOST OF SOUTHERN NEW JERSEY TIL 10 PM EDT... AT 5 15 PM AN AREA OF SHOWERS AND STRONG THUNDERSTORMS EXTENDED FROM WESTERN NEW YORK STATE TO SOUTHWEST NORTH CAROLINA. IN PENNSYLVANIA THE LEADING EDGE OF THE STORMS EXTENDED FROM BRADFORD COUNTY IN THE NORTH TO LANCASTER COUNTY IN THE SOUTH. THE STORMS ARE MOVING EAST NORTHEAST AT 45 MILES AN HOUR. SOME INDIVIDUAL STORMS ARE MOVING AS FAST AS 55 MILES AN HOUR. FOR THE NEXT COUPLE OF HOURS THESE STORMS WILL BE MOVING VERY QUICKLY ACROSS CENTRAL AND EASTERN PENNSYLVANIA AND INTO NEW JERSEY. TORNADOES...STRONG WIND GUSTS...HAIL...AND DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS. STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOCAL RADIO AND TELEVISION STATIONS THIS AFTERNOON AND EVENING FOR ANY ADDITIONAL SEVERE WEATHER WATCHES...WARNINGS OR STATEMENTS. JEJ
Special weather statement, May 6, 5:25 PM EDT, 1 hour 23 minutes before
PAZ007>012-016-NJZ002>004-006-062300- SEVERE WEATHER STATEMENT - NATIONAL WEATHER SERVICE PHILADELPHIA PA 530 PM EDT MON MAY 6 1991 ...TORNADO WATCH IN EFFECT FOR SOUTHEAST PENNSYLVANIA AND MOST OF SOUTHERN NEW JERSEY TIL 10 PM EDT... AT 5 15 PM AN AREA OF SHOWERS AND STRONG THUNDERSTORMS EXTENDED FROM WESTERN NEW YORK STATE TO SOUTHWEST NORTH CAROLINA. IN PENNSYLVANIA THE LEADING EDGE OF THE STORMS EXTENDED FROM BRADFORD COUNTY IN THE NORTH TO LANCASTER COUNTY IN THE SOUTH. THE STORMS ARE MOVING EAST NORTHEAST AT 45 MILES AN HOUR. SOME INDIVIDUAL STORMS ARE MOVING AS FAST AS 55 MILES AN HOUR. FOR THE NEXT COUPLE OF HOURS THESE STORMS WILL BE MOVING VERY QUICKLY ACROSS CENTRAL AND EASTERN PENNSYLVANIA...INCLUDING THE PHILADELPHIA METROPOLITAN AREA...AND INTO SOUTHERN NEW JERSEY. TORNADOES...STRONG WIND GUSTS...HAIL...AND DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS. STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOC AL RADIO AND TELEVISION STATIONS THIS AFTERNOON AND EVENING FOR ANY ADDITIONAL SEVERE WEATHER WATCHES...WARNINGS OR STATEMENTS. JEJ
Special weather statement, May 6, 5:28 PM EDT, 1 hour 20 minutes before
DEZALL-062300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WILMINGTON DE 528 PM EDT MON MAY 6 1991 ...THUNDERSTORMS HEADING FOR THE FIRST STATE... ...TORNADO WATCH IN EFFECT UNTIL 10 PM EDT TONIGHT... AT 515 PM WEATHER RADAR SHOWED A LINE OF THUNDERSTORMS EXTENDING FROM 40 MILES NORTHWEST OF THE NEW CASTLE COUNTY AIRPORT TO 15 MILES WEST OF BALTIMORE TO JUST WEST OF WASHINGTON AND SOUTHWARD INTO VIRGINIA. THESE ARE MOVING EAST AT 30 MPH AND WILL BE REACHING NORTHERN DELAWARE AROUND 630 PM...AND A LITTLE LATER FROM 7PM TO 8PM DOWNSTATE. THESE THUNDERSTORMS HAVE BEEN PRODUCING SOME STRONG GUSTY WINDS AND RADAR INDICATES THE POSSIBILITY OF HAIL IN SOME OF THESE THUNDERSTORMS. IN THE HARRISBURG AREA...WINDS GUSTED TO 52 MPH SHORTLY BEFORE 5PM IN A HEAVY SHOWER...AND AT DULLES AIRPORT WINDS GUSTED TO 40 MPH. NO TORNADOES HAVE BEEN SIGHTED AS YET...BUT A TORNADO WATCH IS IN EFFECT FOR ALL OF DELAWARE UNTIL 10PM. SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE WARNING. PERSONS IN THE WATCH AREA SHOULD BE ALERT AND PREPARED TO TAKE PROTECTIVE MEASURES IMMEDIATELY WHEN THE THUNDERSTORMS REACH THE STATE. LISTEN FOR LATER STATEMENTS OR WARNINGS ON NOAA WEATHER RADIO OR LOCAL TV AND RADIO STATIONS. CS
Special weather statement, May 6, 5:51 PM EDT, 57 minutes before
062145-002-004-062300 SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ATLANTIC CITY NJ 545 PM EDT MON MAY 06 1991 ...TORNADO WATCH IN EFFECT FOR SOUTHERN NEW JERSEY UNTIL 10 PM EDT... NO SEVERE WEATHER HAS BEEN DETECTED OVER SOUTHERN NEW JERSEY AT THIS TIME. AT 430 PM...OUR WEATRHER SEARCH RADAR INDICATED SCATTERED SHOWERS OVER NORTHWEST AND NORTH CENTRAL NEW JERSEY. MOVEMENT WAS MOVING NORTHEAST AT 35 MILES AN HOUR. THUNDERSTORMS...SOME WITH VERY HEAVY RAIN AND HAIL...WERE INDICATED IN THE LOWER SUSQUEHANNA VALLEY OF PENNSYLVANIA MOVING INTO CHESTER COUNTY SOUTHEAST PENNSYLVANIA. STORNG GUSTY WINDS AND FREQUENT LIGHTNING ARE ALSO ASSOCIATED WITH THESE STORM AS THEY MOVE EASTNORTHEAST AT 50 MILES AN HOUR. OTHER SHOWERS AND THUNDERSTORMS EXTENDED FROM BETWEEN WILLIAMSPORT AND ALLENTOWN PENNSYLVANIA DWON THROUGH THE SUSQUEHANNA VALLEY OF PENNSYLVANIA ...SOUTHEAST PENNSYLVANIA AND NORTHERN INTO CENTRAL MARYLAND. THIS AREA WAS MOVING EAST AT 30 MILES AN HOUR. REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES AND SEVERE THUNDERSTORMS TO DEVELOP IN AND CLOSE TO A WATCH AREA. PERSONS IN SOUTHERN NEW JERSEY SHOULD BE ON THE LOOKOUT FOR THREATNING WEJATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. BE PREPARED TO SEEK SHELTER IF SEVERE WEATHER APPROACHES. FXD/WS/PM
Special weather statement, May 6, 6:46 PM EDT, 2 minutes before
NJZ003-004-062355- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ATLANTIC CITY NJ 635 PM EDT MON MAY 06 1991 ...TORNADO WATCH IN EFFECT FOR SOUTHERN NEW JERSEY UNTIL 10 PM EDT... AT 630 PM...RADAR INDICATED A POSSIBLE SEVERE THUNDERSTORM PASSING SALEM SOUTHWEST NEW JERSEY INTO GLOUCESTER COUNTY NEAR WILLIAMSTOWN. HAIL WAS REPORTED WITH THIS STORM OF 3/8 INCH AS IT PASSED WILMINGTON DELAWARE. OTHER THUNDERSTORMS WITH VERY HEAVY RAIN...POSSIBLE HAIL...STRONG GUSTY WINDS TO 60 MPH AND FREQUENT DANGEROUS LIGHTNING EXTENDED ALONG THE NEW JERSEY/PENNSYLVANIA BORDER FROM EASTON TO JUST NORTH OF TRENTON. MOVEMENT WAS EAST TO EASTNORTHEAST AT 55 MILES AN HOUR. ANOTHER STORM WAS INDICATED ON THE EASTERN SHORE OF THE CHESAPEAKE BAY MARYLANDBETWEEN CHESTERTOWN AND CENTERVILLE. OTHER SHOWERS AND THUNDERSTORMS EXTENDED FROM NORTHEAST PENNSYLVANIA INTO EASTERN AND SOUTHEAST PENNSYLVANIA...PUSHING INTO EXTREME WESTERN NEW JERSEY ...NORTHERN AND CENTRAL DELAWARE INTO MARYLAND. THIS AREA WAS MOVING EAST AT 35 MILES AN HOUR...WHILE THE STORM MOVED EASTNORTHEAST AT 50 MILES AN HOUR. REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES AND SEVERE THUNDERSTORMS TO DEVELOP IN AND CLOSE TO A WATCH AREA. PERSONS IN SOUTHERN NEW JERSEY SHOULD BE ON THE LOOKOUT FOR THREATNING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. BE PREPARED TO SEEK SHELTER IF SEVERE WEATHER APPROACHES. FXD/WS
Special weather statement, May 6, 6:48 PM EDT, 0 minutes before
DEZ003-002-001-070045- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WILMINGTON DE 641 PM EDT MON MAY 6 1991 ...THUNDERSTORMS MOVING THROUGH NORTHERN DELAWARE...AND HEADING FOR CENTRAL AND SOUTH
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 6, 5:43 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 32 min |
| May 6, 6:06 PM EDT | Severe Thunderstorm Warning | PHI | Montgomery | 54 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 1991Every severe thunderstorm warning in 1991
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.