Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 129, NWS Philadelphia/Mount Holly

July 6, 20215 counties in Pennsylvania; Burlington County, Camden County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 6, 2021, 6:13 PM EDT for 5 counties in Pennsylvania; Burlington County, Camden County, New Jersey. It was in force for 31 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 6, 2021, 6:13 PM EDT (22:13 UTC)
Expired: Jul 6, 2021, 6:44 PM EDT
In force: 31 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Burlington County, NJ, Camden County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 72 km from the middle of the area, began a volume at 22:15 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.

Issued	Product	Office	Lasted
Jul 6, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.2 hours before the alert went out and 221 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 230 J/kg
Mixed-layer CIN: -195 J/kg
Mixed-layer LCL: 1202 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 139 m²/s²
0-3 km storm-relative helicity: 184 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

433 
WUUS51 KPHI 062213
SVRPHI
NJC005-007-PAC017-029-045-091-101-062300-
/O.NEW.KPHI.SV.W.0129.210706T2213Z-210706T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
613 PM EDT Tue Jul 6 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Camden County in southern New Jersey...
  Northwestern Burlington County in southern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Southeastern Bucks County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  Northeastern Delaware County in southeastern Pennsylvania...

* Until 700 PM EDT.

* At 613 PM EDT, a severe thunderstorm was located over Norristown,
  or 12 miles northwest of Philadelphia, moving east at 30 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Public.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Philadelphia, Camden, Cherry Hill, Bensalem, Evesham, Mount Laurel,
  Norristown, Willingboro, Medford, Phoenixville, West Norriton, East
  Norriton, Lumberton, Florence, Yeadon, Burlington, Bristol, Mount
  Holly, Riverside and Conshohocken.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 6A.
 Pennsylvania Turnpike between mile markers 319 and 359.
 Northeast Extension between mile markers 21 and 27.
 Interstate 95 in Pennsylvania between mile markers 19 and 40.
 Interstate 76 in Pennsylvania between mile markers 327 and 348.
 Interstate 295 in New Jersey between mile markers 34 and 51.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 1 and 4.
 Interstate 476 in Pennsylvania between mile markers 6 and 19.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3997 7557 4021 7552 4021 7478 3986 7477
TIME...MOT...LOC 2213Z 271DEG 27KT 4011 7532 

HAIL...0.75IN
WIND...60MPH
 
$$

Fitzsimmons

2 follow-up statements

360 
WWUS51 KPHI 062235
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
635 PM EDT Tue Jul 6 2021

PAC029-062242-
/O.CAN.KPHI.SV.W.0129.000000T0000Z-210706T2300Z/
Chester PA-
635 PM EDT Tue Jul 6 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CHESTER COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
southern New Jersey...and southeastern Pennsylvania.

LAT...LON 3995 7535 4021 7532 4021 7478 3986 7477
TIME...MOT...LOC 2232Z 271DEG 27KT 4011 7513 

$$

NJC005-007-PAC017-045-091-101-062300-
/O.CON.KPHI.SV.W.0129.000000T0000Z-210706T2300Z/
Camden NJ-Burlington NJ-Montgomery PA-Bucks PA-Philadelphia PA-
Delaware PA-
635 PM EDT Tue Jul 6 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR NORTHWESTERN CAMDEN...NORTHWESTERN BURLINGTON...SOUTHEASTERN
MONTGOMERY...SOUTHEASTERN BUCKS...PHILADELPHIA AND NORTHEASTERN
DELAWARE COUNTIES...

At 632 PM EDT, a severe thunderstorm was located over Jenkintown, or 
near Philadelphia, moving east at 30 mph. This storm has a history 
of producing damage as it moved through Chester County resulting in 
downed trees and wires. 

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Public.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Philadelphia, Camden, Cherry Hill, Bensalem, Mount Laurel,
Norristown, Willingboro, Medford, East Norriton, Lumberton, Florence,
Yeadon, Burlington, Bristol, Mount Holly, Riverside, Conshohocken,
Palmyra, Hatboro and Ambler.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 6A.
 Pennsylvania Turnpike between mile markers 331 and 359.
 Northeast Extension between mile markers 21 and 26.
 Interstate 95 in Pennsylvania between mile markers 20 and 40.
 Interstate 76 in Pennsylvania between mile markers 331 and 347.
 Interstate 295 in New Jersey between mile markers 34 and 51.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 2 and 4.
 Interstate 476 in Pennsylvania between mile markers 7 and 9, and
between mile markers 15 and 19.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3995 7535 4021 7532 4021 7478 3986 7477
TIME...MOT...LOC 2232Z 271DEG 27KT 4011 7513 

HAIL...0.75IN
WIND...60MPH
 
$$

Fitzsimmons

657 
WWUS51 KPHI 062244
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
644 PM EDT Tue Jul 6 2021

NJC005-007-PAC017-045-091-101-062253-
/O.CAN.KPHI.SV.W.0129.000000T0000Z-210706T2300Z/
Camden NJ-Burlington NJ-Montgomery PA-Bucks PA-Philadelphia PA-
Delaware PA-
644 PM EDT Tue Jul 6 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN CAMDEN...
NORTHWESTERN BURLINGTON...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN
BUCKS...PHILADELPHIA AND NORTHEASTERN DELAWARE COUNTIES IS
CANCELLED...
        
The storm which prompted the warning has weakened below severe 
limits, and is exiting the warned area. Therefore, the warning has 
been cancelled.  However gusty winds are still possible with this 
thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
southern New Jersey...and southeastern Pennsylvania.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

LAT...LON 3995 7535 4021 7532 4021 7478 3986 7477
TIME...MOT...LOC 2241Z 271DEG 27KT 4011 7502 

$$

Fitzsimmons

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 6, 4:23 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	52 min
Jul 6, 4:29 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	76 min
Jul 6, 5:08 PM EDT	Special Weather Statement	PHI	Carbon	37 min
Jul 6, 5:11 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	49 min
Jul 6, 5:15 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe, Northampton	60 min
Jul 6, 5:34 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	41 min
Jul 6, 5:55 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh, Northampton	65 min
Jul 6, 6:41 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	64 min
Jul 6, 7:01 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	59 min
Jul 6, 7:50 PM EDT	Special Weather Statement	PHI	Lehigh	25 min
Jul 6, 3:53 AM EDT	Small Craft Advisory	PHI		22 hr
Jul 6, 5:46 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Morris, Somerset, Sussex, Warren	59 min
Jul 6, 6:17 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Monmouth, Somerset	58 min
Jul 6, 6:33 PM EDT	Special Marine Warning	PHI		117 min
Jul 6, 7:59 PM EDT	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Monmouth, Ocean, Somerset	61 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2021 Severe Thunderstorm Warnings in New Jersey, 2021 Every severe thunderstorm warning in 2021

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.