Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 82, NWS Philadelphia/Mount Holly

July 7, 20124 counties in Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 7, 2012, 6:58 PM EDT for 4 counties in Pennsylvania; New Castle County, Delaware. It was in force for 48 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 7, 2012, 6:58 PM EDT (22:58 UTC)
Expired
Jul 7, 2012, 7:46 PM EDT
In force
48 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Berks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 115 km from the middle of the area, began a volume at 23:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 7, 11:41 AM EDTSevere Thunderstorm WatchSPC7 hr
Jul 7, 6:14 PM EDTSevere Thunderstorm WatchSPC3 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.0 hours before the alert went out and 173 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, Washington/Dulle, VA at 12:00Z on 2012-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1804 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2012-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 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
1804 J/kg
Mixed-layer CIN
-87 J/kg
Mixed-layer LCL
1395 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
90 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1

Open this sounding in Storm Lab

The text

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

037 
WUUS51 KPHI 072258
SVRPHI
DEC003-PAC011-029-045-091-080000-
/O.NEW.KPHI.SV.W.0082.120707T2258Z-120708T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
658 PM EDT SAT JUL 7 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL BERKS COUNTY IN EASTERN PENNSYLVANIA...
  NORTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK...
  CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF WEST CHESTER...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  WEST CENTRAL MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 800 PM EDT

* AT 655 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM PHOENIXVILLE TO COATESVILLE TO
  14 MILES WEST OF HONEY BROOK...OR ALONG A LINE EXTENDING FROM 13
  MILES NORTHEAST OF WEST CHESTER TO 11 MILES NORTHWEST OF WEST
  CHESTER TO 7 MILES EAST OF LANCASTER...AND MOVING SOUTHEAST AT 35
  MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  PARKESBURG AND PAOLI AROUND 705 PM EDT...
  WEST CHESTER AND MARSHALLTON AROUND 710 PM EDT...
  NEWTOWN SQUARE...WESTTOWN...GRADYVILLE AND COCHRANVILLE AROUND 715
  PM EDT...
  BROOMALL AND HOMEVILLE AROUND 720 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...LARGE HAIL...AND DEADLY CLOUD TO
GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM EDT
SATURDAY EVENING FOR NORTHERN NEW JERSEY AND EASTERN PENNSYLVANIA. A
SEVERE THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL MIDNIGHT EDT
SUNDAY MORNING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEASTERN PENNSYLVANIA.

&&

LAT...LON 3988 7600 3996 7600 4003 7594 4011 7595
      4014 7589 4019 7596 4028 7561 3985 7526
      3985 7533 3982 7539 3964 7559 3960 7560
      3963 7556 3953 7556 3950 7577 3972 7579
      3972 7600 3980 7606
TIME...MOT...LOC 2258Z 337DEG 31KT 4011 7548 4001 7578
          4002 7615

$$

HAYES
3 follow-up statements
877 
WWUS51 KPHI 072316
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
716 PM EDT SAT JUL 7 2012

PAC011-091-072326-
/O.CAN.KPHI.SV.W.0082.000000T0000Z-120708T0000Z/
BERKS PA-MONTGOMERY PA-
716 PM EDT SAT JUL 7 2012

...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL MONTGOMERY AND
SOUTH CENTRAL BERKS COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE WARNING HAS MOVED OUT OF THE AREA.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT
SUNDAY MORNING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 3988 7600 3996 7600 4003 7594 4011 7595
      4013 7591 4008 7593 4017 7560 3985 7527
      3982 7539 3964 7559 3962 7560 3960 7560
      3963 7556 3953 7556 3950 7577 3972 7579
      3972 7600 3979 7605
TIME...MOT...LOC 2316Z 337DEG 31KT 3996 7541 3987 7571
          3988 7607

$$

DEC003-PAC029-045-080000-
/O.CON.KPHI.SV.W.0082.000000T0000Z-120708T0000Z/
DELAWARE PA-NEW CASTLE DE-CHESTER PA-
716 PM EDT SAT JUL 7 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR CHESTER...NORTHERN NEW CASTLE AND DELAWARE COUNTIES...

AT 714 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM UPPER PROVIDENCE TOWNSHIP TO
KENNETT SQUARE TO HOMEVILLE...OR ALONG A LINE EXTENDING FROM 10 MILES
EAST OF WEST CHESTER TO 8 MILES SOUTHWEST OF WEST CHESTER TO 15 MILES
SOUTHEAST OF LANCASTER...MOVING SOUTHEAST AT 35 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  NETHER PROVIDENCE TOWNSHIP...WOODLYN...SWARTHMORE AND FOLSOM BY 725
  PM EDT...
  EDDYSTONE...RIDLEY PARK...PROSPECT PARK AND LADENBERG BY 730 PM
  EDT...
  WILMINGTON AND STANTON BY 735 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT
SUNDAY MORNING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3988 7600 3996 7600 4003 7594 4011 7595
      4013 7591 4008 7593 4017 7560 3985 7527
      3982 7539 3964 7559 3962 7560 3960 7560
      3963 7556 3953 7556 3950 7577 3972 7579
      3972 7600 3979 7605
TIME...MOT...LOC 2316Z 337DEG 31KT 3996 7541 3987 7571
          3988 7607

$$

HAYES
721 
WWUS51 KPHI 072335
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
735 PM EDT SAT JUL 7 2012

DEC003-PAC029-045-080000-
/O.CON.KPHI.SV.W.0082.000000T0000Z-120708T0000Z/
DELAWARE PA-NEW CASTLE DE-CHESTER PA-
735 PM EDT SAT JUL 7 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR SOUTHERN CHESTER...NORTHERN NEW CASTLE AND DELAWARE COUNTIES...

AT 731 PM EDT...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED.  THESE
STORMS WERE LOCATED ALONG A LINE EXTENDING FROM SWARTHMORE TO ASHLAND
TO COCHRANVILLE...OR ALONG A LINE EXTENDING FROM 12 MILES SOUTHWEST
OF PHILADELPHIA TO 9 MILES SOUTH OF WEST CHESTER TO 18 MILES
NORTHWEST OF NEWARK...MOVING SOUTHEAST AT 30 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
AVONDALE...RUTLEDGE...WEST GROVE...VILLAGE GREEN-GREEN RIDGE...
FOLSOM...BROOKHAVEN...PARKSIDE...WOODLYN...PROSPECT PARK...RIDLEY
PARK...TALLEYVILLE...UPLAND...CHESTER TOWNSHIP...BOOTHWYN...ARDEN...
CHESTER...EDDYSTONE...ARDENTOWN...LINWOOD...ARDENCROFT...TRAINER...
HOCKESSIN...CLAYMONT...MARCUS HOOK...LADENBERG...BELLEFONTE...NORTH
STAR...EDGEMOOR...KEMBLESVILLE...ELSMERE...SAINT GEORGES...MOUNT
PLEASANT...GLASGOW...BEAR...WILMINGTON MANOR...WILMINGTON...
STANTON...PIKE CREEK...NEWPORT...NEW CASTLE...DELAWARE CITY AND
BROOKSIDE

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT
SUNDAY MORNING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 3993 7596 4008 7552 3985 7527 3985 7533
      3982 7539 3964 7559 3960 7560 3963 7556
      3953 7556 3950 7577 3972 7579 3973 7591
      3988 7597
TIME...MOT...LOC 2335Z 316DEG 18KT 3992 7532 3983 7563
          3984 7599

$$

HAYES
845 
WWUS51 KPHI 072346
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
746 PM EDT SAT JUL 7 2012

DEC003-PAC029-045-072355-
/O.CAN.KPHI.SV.W.0082.000000T0000Z-120708T0000Z/
DELAWARE PA-NEW CASTLE DE-CHESTER PA-
746 PM EDT SAT JUL 7 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN CHESTER...NORTHERN
NEW CASTLE AND SOUTHWESTERN DELAWARE COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO LONGER 
EXPECTED TO PRODUCE SEVERE WEATHER.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT
SUNDAY MORNING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 3993 7596 4008 7552 3985 7527 3985 7533
      3982 7539 3964 7559 3960 7560 3963 7556
      3953 7556 3950 7577 3972 7579 3973 7591
      3988 7597
TIME...MOT...LOC 2345Z 316DEG 18KT 3988 7528 3979 7559
          3980 7595

$$

HAYES

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 4:49 PM EDTSpecial Weather StatementPHIBerks, Carbon, Lehigh, Northampton86 min
Jul 7, 5:07 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton53 min
Jul 7, 5:57 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Delaware, Lehigh, Montgomery and 2 more63 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2012Severe Thunderstorm Warnings in Delaware, 2012Every severe thunderstorm warning in 2012

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; radar from the NEXRAD Level II archive.