Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 122, NWS Philadelphia/Mount Holly

November 18, 20135 counties in Pennsylvania; New Castle County, Delaware; Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 18, 2013, 2:28 AM EST for 5 counties in Pennsylvania; New Castle County, Delaware; Cecil County, Maryland. It was in force for 62 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Nov 18, 2013, 2:28 AM EST (07:28 UTC)
Expired
Nov 18, 2013, 3:30 AM EST
In force
62 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Cecil County, MD, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 120 km from the middle of the area, began a volume at 07:30 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.

What was reported inside it

TimeReportWhereRemark
Nov 18, 2:35 AM ESTTSTM WND GST 52Reading Airport, PA
Nov 18, 3:09 AM ESTTSTM WND DMGNewark, DEWIRES REPORTED DOWN.
Nov 18, 3:25 AM ESTTSTM WND DMGUpper Merion Twp, PATREE REPORTED DOWN.
Nov 18, 3:29 AM ESTTSTM WND DMGNorristown, PAPOWER LINES REPORTED DOWN ON PINE STREET IN NORRISTOWN

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

IssuedProductOfficeLasted
Nov 18, 1:07 AM ESTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 7.5 hours before the alert went out and 184 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 00:00Z on 2013-11-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2013-11-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 308 square meters per square second.19395878Sfc1 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
697 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
308 m²/s²
0-3 km storm-relative helicity
340 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.

353 
WUUS51 KPHI 180728
SVRPHI
DEC003-MDC015-PAC011-017-029-045-091-180830-
/O.NEW.KPHI.SV.W.0122.131118T0728Z-131118T0830Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
228 AM EST MON NOV 18 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  WESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  NORTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  NORTHERN CECIL COUNTY IN NORTHEAST MARYLAND...
  CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 330 AM EST

* AT 226 AM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS. THESE SEVERE STORMS EXTENDED FROM
  LEESPORT TO LEOLA TO WHITEFORD...MOVING EAST AT 70 MPH. THESE
  STORMS ARE CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  HONEY BROOK AND NEW MORGAN AROUND 235 AM EST...
  PARKESBURG AND OXFORD AROUND 240 AM EST...
  GILBERTSVILLE AND EAST GREENVILLE AROUND 245 AM EST...
  SCHWENKSVILLE AND WEST GROVE AROUND 250 AM EST...
  NEWARK AND PHOENIXVILLE AROUND 255 AM EST...
  WILMINGTON MANOR AND TALLEYVILLE AROUND 300 AM EST...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 500 AM EST MONDAY
MORNING FOR NORTHWEST NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 3973 7614 3979 7605 3988 7599 3997 7600
      4004 7594 4011 7595 4014 7589 4029 7613
      4047 7602 4046 7555 4042 7548 4046 7544
      4045 7507 4041 7504 4009 7522 3968 7554
      3966 7617 3969 7621 3972 7622
TIME...MOT...LOC 0727Z 269DEG 61KT 4044 7590 4005 7616
          3973 7633

$$

FORECASTER: HEAVENER
2 follow-up statements
154 
WWUS51 KPHI 180804
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
304 AM EST MON NOV 18 2013

DEC003-MDC015-PAC011-017-029-045-091-180830-
/O.CON.KPHI.SV.W.0122.000000T0000Z-131118T0830Z/
BERKS PA-BUCKS PA-MONTGOMERY PA-DELAWARE PA-NEW CASTLE DE-CECIL MD-
CHESTER PA-
304 AM EST MON NOV 18 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 AM EST
FOR CHESTER...NORTHERN CECIL...NORTHERN NEW CASTLE...DELAWARE...
MONTGOMERY...WESTERN BUCKS AND SOUTHERN BERKS COUNTIES...

AT 301 AM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM TRUMBAUERSVILLE TO CHESTER SPRINGS TO GLEN WESTOVER...
MOVING EAST AT 70 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
WILMINGTON MANOR AND TALLEYVILLE AROUND 310 AM EST...
TINICUM AND TINICUM TOWNSHIP AROUND 315 AM EST...
MAPLE GLEN AND FORT WASHINGTON AROUND 320 AM EST...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 AM EST MONDAY
MORNING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA.

&&

LAT...LON 3973 7614 3979 7605 3988 7599 3997 7600
      4004 7594 4011 7595 4014 7589 4029 7613
      4047 7602 4046 7555 4042 7548 4046 7544
      4045 7507 4041 7504 4009 7522 3968 7554
      3966 7617 3969 7621 3972 7622
TIME...MOT...LOC 0804Z 269DEG 61KT 4044 7533 4008 7555
          3971 7574

$$

KLINE
355 
WWUS51 KPHI 180817
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
317 AM EST MON NOV 18 2013

MDC015-PAC011-180826-
/O.CAN.KPHI.SV.W.0122.000000T0000Z-131118T0830Z/
BERKS PA-CECIL MD-
317 AM EST MON NOV 18 2013

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CECIL AND SOUTHERN
BERKS COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE SEVERE THUNDERSTORM WARNING HAS MOVED OUT
OF THE AREA...THEREFORE THE SEVERE THUNDERSTORM WARNING HAS BEEN
CANCELLED.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 AM EST MONDAY
MORNING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA. A SEVERE THUNDERSTORM WATCH ALSO REMAINS IN
EFFECT UNTIL 800 AM EST MONDAY MORNING FOR NORTHEAST NEW JERSEY.

LAT...LON 4013 7549 4046 7528 4045 7507 4040 7504
      4009 7522 4006 7526 4003 7526 3971 7551
      3968 7554 3968 7574
TIME...MOT...LOC 0816Z 269DEG 61KT 4043 7519 4013 7538
          3969 7562

$$

DEC003-PAC017-029-045-091-180830-
/O.CON.KPHI.SV.W.0122.000000T0000Z-131118T0830Z/
BUCKS PA-MONTGOMERY PA-DELAWARE PA-NEW CASTLE DE-CHESTER PA-
317 AM EST MON NOV 18 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 AM EST
FOR EAST CENTRAL CHESTER...NORTHERN NEW CASTLE...DELAWARE...CENTRAL
MONTGOMERY AND WESTERN BUCKS COUNTIES...

AT 315 AM EST...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED CAPABLE
OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM BEDMINSTER TO TROOPER TO
STANTON...MOVING EAST AT 70 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
MAPLE GLEN AND FORT WASHINGTON AROUND 325 AM EST...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 AM EST MONDAY
MORNING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA.

&&

LAT...LON 4013 7549 4046 7528 4045 7507 4040 7504
      4009 7522 4006 7526 4003 7526 3971 7551
      3968 7554 3968 7574
TIME...MOT...LOC 0816Z 269DEG 61KT 4043 7519 4013 7538
          3969 7562

$$

KLINE

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 18, 1:58 AM ESTSevere Thunderstorm WarningPHIBerks, Bucks, Carbon, Lehigh, Monroe, Northampton62 min
Nov 18, 2:54 AM ESTSevere Thunderstorm WarningPHIBucks, Lehigh, Monroe, Northampton66 min
Nov 18, 3:29 AM ESTSevere Thunderstorm WarningPHIBucks, Delaware, Montgomery, Philadelphia61 min
Nov 18, 2:46 AM ESTSevere Thunderstorm WarningPHIKent, New Castle59 min
Nov 18, 3:39 AM ESTSevere Thunderstorm WarningPHIKent, New Castle, Sussex66 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2013Severe Thunderstorm Warnings in Delaware, 2013Severe Thunderstorm Warnings in Maryland, 2013Every severe thunderstorm warning in 2013

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.