Alert archive / New Jersey / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 117, NWS Philadelphia/Mount Holly

November 1, 20135 counties in Pennsylvania; 6 counties in New Jersey; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 1, 2013, 8:37 AM EDT for 5 counties in Pennsylvania; 6 counties in New Jersey; New Castle County, Delaware. It was in force for 68 min. 12 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 1, 2013, 8:37 AM EDT (12:37 UTC)
Expired
Nov 1, 2013, 9:45 AM EDT
In force
68 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Hunterdon County, NJ, Mercer County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 89 km from the middle of the area, began a volume at 12:39 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 1, 8:45 AM EDTTSTM WND GST 52Spring Mount, PA
Nov 1, 8:50 AM EDTTSTM WND GST 47Stewartsville, NJ
Nov 1, 8:55 AM EDTTSTM WND DMGEagleville, PATREE DOWN
Nov 1, 9:05 AM EDTTSTM WND DMGEast Whiteland Twp, PATREE FELL ONTO A ROOFTOP
Nov 1, 9:12 AM EDTTSTM WND DMGOxford, NJBRIEF POWER OUTAGES ACROSS WARREN COUNTY
Nov 1, 9:15 AM EDTTSTM WND DMGHaverford Twp, PAA FEW FEW LARGE TREE LIMBS DOWN.
Nov 1, 9:15 AM EDTTSTM WND DMGPittstown, NJTREES DOWN
Nov 1, 9:20 AM EDTTSTM WND DMGBedminster, NJTREES DOWN.
Nov 1, 9:20 AM EDTTSTM WND DMGBoonton, NJTREES AND WIRES DOWN THROUGHOUT THE COUNTY.
Nov 1, 9:25 AM EDTTSTM WND DMGGreenville, DEWIRES DOWN.
Nov 1, 9:32 AM EDTTSTM WND GST 48Philadelphia Intl Airpo, PA
Nov 1, 9:52 AM EDTTSTM WND DMGOxford, NJBRIEF POWER OUTAGES ACROSS WARREN COUNTY

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 1, 6:25 AM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 0.6 hours before the alert went out and 162 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, Brookhaven, NY at 12:00Z on 2013-11-01Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2013-11-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 334 square meters per square second.1939587897Sfc1 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
908 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
334 m²/s²
0-3 km storm-relative helicity
380 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.

882 
WUUS51 KPHI 011237
SVRPHI
DEC003-NJC019-021-027-035-037-041-PAC017-029-045-091-101-011345-
/O.NEW.KPHI.SV.W.0117.131101T1237Z-131101T1345Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
837 AM EDT FRI NOV 1 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WARREN COUNTY IN NORTHWEST NEW JERSEY...
  HUNTERDON COUNTY IN NORTHWEST NEW JERSEY...
  WESTERN MERCER COUNTY IN CENTRAL NEW JERSEY...
  MORRIS COUNTY IN NORTHERN NEW JERSEY...
  SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  SOUTHERN SUSSEX COUNTY IN NORTHWEST NEW JERSEY...
  BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  NORTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 945 AM EDT

* AT 832 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A LINE OF HEAVY SHOWERS AND ISOLATED THUNDERSTORMS. THIS LINE
  EXTENDED FROM HIDDEN LAKE TO LEHIGH UNIVERSITY TO GREEN LANE TO    
  HONEY BROOK TO GLEN ROY...MOVING EAST AT 50 MPH. THIS LINE IS      
  CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. 

THERE IS LITTLE TO NO LIGHTNING BEING DETECTED WITH THIS LINE, 
HOWEVER VERY STRONG WINDS JUST ABOVE THE SURFACE CAN MIX DOWN WITH 
THE LINE AS IT MOVES THROUGH RESULTING IN WIND DAMAGE.

* LOCATIONS IMPACTED INCLUDE...
  FIVE POINTS...
  WEST GROVE...
  KENNETT SQUARE...
  FRANKLIN...
  HAMBURG...
  CONCORDVILLE...
  BRYN MAWR...
  WILLOW GROVE...
  GERMANTOWN...
  WOODSIDE...
  MILLSTONE...
  LEVITTOWN...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS LINE MAY CONTAIN LITTLE OR NO LIGHTNING. DO NOT WAIT TO HEAR 
THUNDER BEFORE TAKING COVER. SEEK SHELTER IMMEDIATELY INSIDE A 
STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1100 AM EDT
FRIDAY MORNING FOR NORTHWESTERN NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4118 7439 4109 7450 4104 7450 4105 7445
      4102 7443 4100 7430 4091 7427 4090 7433
      4076 7436 4058 7452 4019 7475 3984 7528
      3984 7535 3971 7550 3972 7608 4061 7520
      4106 7502 4109 7497 4109 7499
TIME...MOT...LOC 1235Z 263DEG 42KT 4107 7493 4062 7531
          4032 7543 4006 7577 3974 7601

$$

FORECASTER: GORSE
2 follow-up statements
525 
WWUS51 KPHI 011301
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
901 AM EDT FRI NOV 1 2013

DEC003-NJC019-021-027-035-037-041-PAC017-029-045-091-101-011345-
/O.CON.KPHI.SV.W.0117.000000T0000Z-131101T1345Z/
WARREN NJ-HUNTERDON NJ-MERCER NJ-MORRIS NJ-SOMERSET NJ-SUSSEX NJ-
BUCKS PA-MONTGOMERY PA-PHILADELPHIA PA-DELAWARE PA-NEW CASTLE DE-
CHESTER PA-
901 AM EDT FRI NOV 1 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 AM EDT
FOR EASTERN CHESTER...NORTHERN NEW CASTLE...DELAWARE...
PHILADELPHIA...MONTGOMERY...BUCKS...SOUTHERN SUSSEX...SOMERSET...
MORRIS...WESTERN MERCER...HUNTERDON AND EASTERN WARREN COUNTIES...

AT 858 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
TRACK A LINE OF HEAVY SHOWERS AND ISOLATED THUNDERSTORMS PRODUCING
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS LINE EXTENDED FROM FRANKLIN 
TO BLOOMSBURY TO ROBESONIA TO VALLEY FORGE TO KEMBLESVILLE...MOVING 
EAST AT 50 MPH.

THERE IS LITTLE TO NO LIGHTNING BEING DETECTED WITH THIS LINE, 
HOWEVER VERY STRONG WINDS JUST ABOVE THE SURFACE ARE MIXING DOWN 
WITH THE LINE AS IT MOVES THROUGH RESULTING IN AREAS OF WIND DAMAGE.

LOCATIONS IMPACTED INCLUDE...
KING OF PRUSSIA...
CONCORDVILLE...
EDGEMOOR...
WILLOW GROVE...
EAST LANSDOWNE...
WOODSIDE...
HOLMESBURG...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS LINE HAS A HISTORY OF PRODUCING DAMAGING WINDS. SEEK SHELTER 
NOW INSIDE A STURDY STRUCTURE, AND STAY AWAY FROM WINDOWS.

THIS LINE MAY CONTAIN LITTLE OR NO LIGHTNING. DO NOT WAIT TO HEAR 
THUNDER BEFORE TAKING COVER. SEEK SHELTER IMMEDIATELY INSIDE A 
STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1100 AM EDT
FRIDAY MORNING FOR NORTHWESTERN NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4118 7439 4109 7450 4104 7450 4100 7430
      4091 7427 4090 7433 4076 7436 4058 7452
      4019 7475 3985 7526 3984 7536 3971 7550
      3972 7599 4060 7515 4109 7490
TIME...MOT...LOC 1258Z 263DEG 42KT 4110 7460 4065 7498
          4035 7510 4009 7544 3974 7580

$$

FORECASTER: GORSE
327 
WWUS51 KPHI 011344
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
944 AM EDT FRI NOV 1 2013

DEC003-NJC019-021-027-035-037-041-PAC017-029-045-091-101-011353-
/O.EXP.KPHI.SV.W.0117.000000T0000Z-131101T1345Z/
WARREN NJ-HUNTERDON NJ-MERCER NJ-MORRIS NJ-SOMERSET NJ-SUSSEX NJ-
BUCKS PA-MONTGOMERY PA-PHILADELPHIA PA-DELAWARE PA-NEW CASTLE DE-
CHESTER PA-
944 AM EDT FRI NOV 1 2013

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN CHESTER...NORTHERN NEW
CASTLE...DELAWARE...PHILADELPHIA...MONTGOMERY...BUCKS...SOUTHERN
SUSSEX...SOMERSET...MORRIS...WESTERN MERCER...HUNTERDON AND EASTERN
WARREN COUNTIES WILL EXPIRE AT 945 AM EDT...

THE LINE OF HEAVY SHOWERS AND ISOLATED THUNDERSTORMS WITH STRONG TO 
DAMAGING WINDS IS EXITING THE AREA, THEREFORE THE SEVERE 
THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL NOON EDT FRIDAY
FOR NEW JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 4118 7439 4109 7450 4104 7450 4100 7430
      4091 7427 4090 7433 4076 7436 4058 7452
      4019 7475 3985 7526 3984 7536 3971 7550
      3972 7599 4060 7515 4109 7490
TIME...MOT...LOC 1343Z 263DEG 42KT 4116 7391 4071 7429
          4041 7442 4015 7476 3981 7512

$$

FORECASTER: GORSE

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 1, 2:21 AM EDTSpecial Weather StatementPHILehigh, Northampton84 min
Nov 1, 3:14 AM EDTWind AdvisoryPHIBerks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more9 hr
Nov 1, 6:45 AM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe75 min
Nov 1, 7:53 AM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more67 min
Nov 1, 9:11 AM EDTSevere Thunderstorm WarningPHIBucks, Philadelphia79 min
Nov 1, 9:25 AM EDTSevere Thunderstorm WarningPHICumberland, Salem65 min
Nov 1, 10:09 AM EDTSpecial Marine WarningPHI81 min
Nov 1, 10:29 AM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Cumberland, Monmouth, Ocean76 min
Nov 1, 1:40 PM EDTSmall Craft AdvisoryPHI3 days
Nov 1, 8:27 AM EDTSevere Thunderstorm WarningPHINew Castle63 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2013Severe Thunderstorm Warnings in Pennsylvania, 2013Severe Thunderstorm Warnings in Delaware, 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.