Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 158, NWS Philadelphia/Mount Holly

September 6, 2014Bucks County, Montgomery County, Pennsylvania; Hunterdon County, Mercer County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 6, 2014, 3:45 PM EDT for Bucks County, Montgomery County, Pennsylvania; Hunterdon County, Mercer County, New Jersey. It was in force for 60 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
Sep 6, 2014, 3:45 PM EDT (19:45 UTC)
Expired
Sep 6, 2014, 4:45 PM EDT
In force
60 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Hunterdon County, NJ, Mercer County, NJ, Bucks County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 76 km from the middle of the area, began a volume at 19:48 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
Sep 6, 2:07 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.8 hours before the alert went out and 193 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 2014-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1867 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 2014-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 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
1867 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
709 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
103 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.0

Open this sounding in Storm Lab

The text

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

623 
WUUS51 KPHI 061945
SVRPHI
NJC019-021-PAC017-091-062045-
/O.NEW.KPHI.SV.W.0158.140906T1945Z-140906T2045Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
345 PM EDT SAT SEP 6 2014

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN HUNTERDON COUNTY IN NORTHWEST NEW JERSEY...
  NORTHWESTERN MERCER COUNTY IN CENTRAL NEW JERSEY...
  CENTRAL BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  CENTRAL MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 445 PM EDT

* AT 344 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM. THE STORM WAS NEAR SILVERDALE...MOVING EAST AT
  20 MPH. THIS STORM IS CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH. 

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  FRICKS AND CHALFONT AROUND 350 PM EDT...
  DUBLIN AROUND 355 PM EDT...
  ROBESONIA AND DOYLESTOWN AROUND 405 PM EDT...
  GARDENVILLE AND PIPERSVILLE AROUND 410 PM EDT...
  TINICUM AROUND 415 PM EDT...
  BYRAM AND ERWINNA AROUND 420 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
SATURDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4057 7482 4025 7476 4021 7546 4041 7551
TIME...MOT...LOC 1945Z 259DEG 18KT 4032 7527

$$

FORECASTER: SFJ
3 follow-up statements
474 
WWUS51 KPHI 062007
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
407 PM EDT SAT SEP 6 2014

PAC091-062016-
/O.CAN.KPHI.SV.W.0158.000000T0000Z-140906T2045Z/
MONTGOMERY PA-
407 PM EDT SAT SEP 6 2014

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL MONTGOMERY COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE COUNTY. 
THUS...THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
SATURDAY EVENING FOR NORTHEAST NEW JERSEY. A SEVERE THUNDERSTORM
WATCH ALSO REMAINS IN EFFECT UNTIL 900 PM EDT SATURDAY EVENING FOR
DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

LAT...LON 4023 7517 4047 7526 4057 7482 4025 7477
TIME...MOT...LOC 2006Z 259DEG 18KT 4041 7505

$$

NJC019-021-PAC017-062045-
/O.CON.KPHI.SV.W.0158.000000T0000Z-140906T2045Z/
HUNTERDON NJ-MERCER NJ-BUCKS PA-
407 PM EDT SAT SEP 6 2014

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM EDT
FOR CENTRAL BUCKS...NORTHWESTERN MERCER AND SOUTHERN HUNTERDON
COUNTIES...

AT 404 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR BYRAM...OR 21 MILES SOUTH OF EASTON...MOVING EAST AT 20
MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  STOCKTON BY 415 PM EDT...
  LAMBERTVILLE AND NEW HOPE BY 420 PM EDT...
  SERGEANTSVILLE BY 425 PM EDT...
  SAND BROOK BY 430 PM EDT...
  FLEMINGTON AND 9 MILES NORTH OF PENNINGTON BY 440 PM EDT...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
SATURDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 4023 7517 4047 7526 4057 7482 4025 7477
TIME...MOT...LOC 2006Z 259DEG 18KT 4041 7505

$$

SFJ
137 
WWUS51 KPHI 062034
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
434 PM EDT SAT SEP 6 2014

PAC017-062044-
/O.CAN.KPHI.SV.W.0158.000000T0000Z-140906T2045Z/
BUCKS PA-
434 PM EDT SAT SEP 6 2014

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BUCKS COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE COUNTY. 
THUS THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
SATURDAY EVENING FOR NORTHEAST NEW JERSEY. A SEVERE THUNDERSTORM
WATCH ALSO REMAINS IN EFFECT UNTIL 900 PM EDT SATURDAY EVENING FOR
DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

LAT...LON 4025 7483 4052 7503 4057 7482 4025 7477
TIME...MOT...LOC 2034Z 259DEG 18KT 4044 7487

$$

NJC019-021-062045-
/O.CON.KPHI.SV.W.0158.000000T0000Z-140906T2045Z/
HUNTERDON NJ-MERCER NJ-
434 PM EDT SAT SEP 6 2014

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM EDT
FOR NORTHWESTERN MERCER AND SOUTHERN HUNTERDON COUNTIES...

AT 436 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR SAND BROOK...OR 16 MILES NORTH OF TRENTON...MOVING EAST
AT 20 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  FLEMINGTON AND 8 MILES NORTH OF PENNINGTON BY 440 PM EDT...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
SATURDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 4025 7483 4052 7503 4057 7482 4025 7477
TIME...MOT...LOC 2034Z 259DEG 18KT 4044 7487

$$

SFJ
997 
WWUS51 KPHI 062039
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
439 PM EDT SAT SEP 6 2014

NJC019-021-062047-
/O.EXP.KPHI.SV.W.0158.000000T0000Z-140906T2045Z/
HUNTERDON NJ-MERCER NJ-
439 PM EDT SAT SEP 6 2014

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN MERCER AND
SOUTHERN HUNTERDON COUNTIES WILL EXPIRE AT 445 PM EDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED. THUS...THE 
WARNING WILL BE ALLOWED TO EXPIRE AT 445 PM EDT.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
SATURDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 4025 7483 4052 7503 4057 7482 4025 7477
TIME...MOT...LOC 2037Z 259DEG 18KT 4044 7485

$$

SFJ

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 1:37 PM EDTSpecial Weather StatementPHINorthampton53 min
Sep 6, 2:13 PM EDTSpecial Weather StatementPHIChester62 min
Sep 6, 2:19 PM EDTSevere Thunderstorm WarningPHIChester43 min
Sep 6, 2:43 PM EDTAreal Flood AdvisoryPHIChester4 hr
Sep 6, 3:21 PM EDTSpecial Weather StatementPHIBerks, Bucks, Lehigh, Montgomery54 min
Sep 6, 3:51 PM EDTFlash Flood WarningPHIChester4 hr
Sep 6, 4:52 PM EDTSevere Thunderstorm WarningPHIDelaware36 min
Sep 6, 7:36 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton54 min
Sep 6, 1:46 PM EDTSpecial Weather StatementPHISussex59 min
Sep 6, 2:58 PM EDTAreal Flood AdvisoryPHIHunterdon, Mercer, Middlesex, Somerset4 hr
Sep 6, 3:19 PM EDTSpecial Weather StatementPHIMiddlesex26 min
Sep 6, 3:25 PM EDTSpecial Weather StatementPHIMercer65 min
Sep 6, 3:32 PM EDTSpecial Weather StatementPHIHunterdon58 min
Sep 6, 4:03 PM EDTSevere Thunderstorm WarningPHIMercer, Middlesex, Monmouth57 min
Sep 6, 4:19 PM EDTSpecial Marine WarningPHI56 min
Sep 6, 4:45 PM EDTSpecial Weather StatementPHIHunterdon, Mercer, Middlesex, Morris, Somerset60 min
Sep 6, 4:47 PM EDTSpecial Weather StatementPHIBurlington58 min
Sep 6, 4:54 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean43 min
Sep 6, 4:58 PM EDTSpecial Marine WarningPHI62 min
Sep 6, 5:09 PM EDTSpecial Marine WarningPHI66 min
Sep 6, 5:26 PM EDTSpecial Marine WarningPHI64 min
Sep 6, 5:31 PM EDTSpecial Weather StatementPHIBurlington59 min
Sep 6, 5:44 PM EDTSevere Thunderstorm WarningPHIBurlington, Ocean35 min
Sep 6, 6:41 PM EDTSpecial Weather StatementPHISalem64 min
Sep 6, 7:41 PM EDTSpecial Marine WarningPHI64 min
Sep 6, 7:45 PM EDTSpecial Weather StatementPHICape May60 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2014Severe Thunderstorm Warnings in New Jersey, 2014Every severe thunderstorm warning in 2014

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.