Alert archive / New Jersey / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 116, NWS Philadelphia/Mount Holly

July 1, 2009Bucks County, Pennsylvania; Burlington County, Mercer County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 1, 2009, 7:05 PM EDT for Bucks County, Pennsylvania; Burlington County, Mercer County, New Jersey. It was in force for 55 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 1, 2009, 7:05 PM EDT (23:05 UTC)
Expired
Jul 1, 2009, 8:00 PM EDT
In force
55 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Burlington County, NJ, Mercer County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 33 km from the middle of the area, began a volume at 23:06 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 nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 11.1 hours before the alert went out and 139 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, Phillips Aaf/Abe, MD at 12:00Z on 2009-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 303 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2009-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 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
303 J/kg
Mixed-layer CIN
-83 J/kg
Mixed-layer LCL
1065 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
131 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 012305
SVRPHI
NJC005-021-PAC017-020000-
/O.NEW.KPHI.SV.W.0116.090701T2305Z-090702T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
705 PM EDT WED JUL 1 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL MERCER COUNTY IN CENTRAL NEW JERSEY...
  EXTREME SOUTHEASTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  NORTH CENTRAL BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 800 PM EDT

* AT 703 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  ANOTHER SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE 
  HAIL...AND  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS    
  LOCATED NEAR JACKSONVILLE...OR 10 MILES SOUTH OF TRENTON...AND  
  MOVING  NORTHEAST   AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  JOBSTOWN AROUND 710 PM EDT...
  FLORENCE AROUND 715 PM EDT...
  BORDENTOWN AROUND 745 PM EDT...
  CROSSWICKS AND WHITE HORSE AROUND 800 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4022 7470 4016 7462 3999 7472 4006 7486
TIME...MOT...LOC 2304Z 222DEG 8KT 4008 7478

$$
 
TFG
1 follow-up statement
000 
WWUS51 KPHI 012334
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
734 PM EDT WED JUL 1 2009

PAC017-012343-
/O.CAN.KPHI.SV.W.0116.000000T0000Z-090702T0000Z/
BUCKS PA-
734 PM EDT WED JUL 1 2009

...THE SEVERE THUNDERSTORM WARNING FOR EXTREME SOUTHEASTERN BUCKS
COUNTY IS CANCELLED...

THE SEVERE STORM HAS REMAINED IN BURLINGTON COUNTY.

LAT...LON 3999 7472 4006 7486 4012 7480 4013 7478
      4012 7476 4015 7472 4018 7474 4022 7470
      4016 7462
TIME...MOT...LOC 2333Z 280DEG 5KT 4007 7472

$$

NJC005-021-020000-
/O.CON.KPHI.SV.W.0116.000000T0000Z-090702T0000Z/
MERCER NJ-BURLINGTON NJ-
734 PM EDT WED JUL 1 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR NORTH CENTRAL BURLINGTON AND SOUTH CENTRAL MERCER COUNTIES...

AT 733 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR JACKSONVILLE...OR 11 MILES SOUTH OF TRENTON...MOVING 
EAST AT 5 MPH. THIS STORM WILL ALSO PRODUCE TORRENTIAL DOWNPOURS
AND CAUSE POOR DRAINAGE FLOODING.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  8 MILES SOUTH OF YARDVILLE-GROVEVILLE BY 750 PM EDT...
  JOBSTOWN BY 755 PM EDT...
  6 MILES SOUTH OF CROSSWICKS BY 800 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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


LAT...LON 3999 7472 4006 7486 4012 7480 4013 7478
      4012 7476 4015 7472 4018 7474 4022 7470
      4016 7462
TIME...MOT...LOC 2333Z 280DEG 5KT 4007 7472

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 1, 10:17 AM EDTSpecial Marine WarningPHI58 min
Jul 1, 10:34 AM EDTSpecial Marine WarningPHI56 min
Jul 1, 1:26 PM EDTSpecial Marine WarningPHI2 hr
Jul 1, 6:55 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean65 min
Jul 1, 7:38 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean67 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2009Severe Thunderstorm Warnings in Pennsylvania, 2009Every severe thunderstorm warning in 2009

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.