Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 169, NWS Philadelphia/Mount Holly

July 12, 20214 counties in Pennsylvania; Burlington County, Camden County, Mercer County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 12, 2021, 5:08 PM EDT for 4 counties in Pennsylvania; Burlington County, Camden County, Mercer County, New Jersey. It was in force for 67 min. 16 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: Jul 12, 2021, 5:08 PM EDT (21:08 UTC)
Expired: Jul 12, 2021, 6:15 PM EDT
In force: 67 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, Mercer County, NJ, Bucks County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 36 km from the middle of the area, began a volume at 21:11 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

Time	Report	Where	Remark
Jul 12, 5:08 PM EDT	TSTM WND DMG	1 Ene Levittown, PA	DOWNED WIRES IN SEVERAL LOCATIONS EAST OF LEVITTOWN. TIME ESTIMATED FROM RADAR.
Jul 12, 5:09 PM EDT	TSTM WND DMG	1 W Tacony, PA	DOWNED WIRES NEAR FRANKFORD AVENUE. TIME ESTIMATED FROM RADAR.
Jul 12, 5:10 PM EDT	TSTM WND DMG	1 Ese Somerton, PA	DOWNED TREE ON U.S. HIGHWAY 1 NEAR SOUTHAMPTON ROAD. TIME ESTIMATED FROM RADAR.
Jul 12, 5:11 PM EDT	TSTM WND DMG	1 Ne Croydon, PA	SEVERAL REPORTS OF DOWNED POWER LINES IN THE CROYDON AND BRISTOL AREAS. TIME ESTIMATED FROM RADAR.
Jul 12, 5:11 PM EDT	TSTM WND DMG	1 Sw Morrisville, PA	DOWNED TREE LIMBS AND WIRES NEAR BRIDGE STREET. TIME ESTIMATED FROM RADAR.
Jul 12, 5:11 PM EDT	TSTM WND DMG	Fairless Hills, PA	MULTIPLE REPORTS OF DOWNED TREES AND WIRES IN FAIRLESS HILLS, ESPECIALLY NEAR BEAUMONT ROAD. TIME ESTIMATED FROM RADAR.
Jul 12, 5:18 PM EDT	TSTM WND DMG	1 E Beverly, NJ	WIRES DOWN ON LINCOLN AVE. TIME ESTIMATED FROM RADAR AND SCANNER REPORT.
Jul 12, 5:21 PM EDT	TSTM WND DMG	1 E Feltonville, PA	DOWNED WIRES NEAR ROSEHILL STREET. TIME ESTIMATED FROM RADAR.
Jul 12, 5:24 PM EDT	TSTM WND DMG	1 Se Eddington, PA	DOWNED POWER LINES NEAR STATE ROAD. TIME ESTIMATED FROM RADAR.
Jul 12, 5:27 PM EDT	TSTM WND DMG	1 E Beverly, NJ	DOWNED WIRES ON LINCOLN AVENUE. TIME ESTIMATED FROM RADAR.
Jul 12, 5:29 PM EDT	TSTM WND DMG	Roebling, NJ	WIRES DOWN ON HAMILTON AVE. TIME ESTIMATED FROM RADAR.
Jul 12, 5:32 PM EDT	TSTM WND DMG	1 N Richmond, PA	DOWNED WIRES NEAR GLENDALE STREET AND BRISTOL STREET. TIME ESTIMATED FROM RADAR.
Jul 12, 5:35 PM EDT	TSTM WND DMG	2 E Willingboro, NJ	DOWNED TREE LIMBS AND WIRES NEAR NEW CASTLE LANE. TIME ESTIMATED FROM RADAR.
Jul 12, 5:40 PM EDT	TSTM WND DMG	1 Ese Jacksonville, NJ	DOWNED WIRES NEAR WARNER ROAD. TIME ESTIMATED FROM RADAR.
Jul 12, 6:09 PM EDT	TSTM WND DMG	1 Nnw Fellowship, NJ	DOWNED WIRES NEAR KINGS HIGHWAY. TIME ESTIMATED FROM RADAR.
Jul 12, 6:12 PM EDT	TSTM WND DMG	1 Sw Moorestown Twp, NJ	DOWNED WIRES NEAR SPRINGHOUSE LANE. TIME ESTIMATED FROM RADAR.

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.

Issued	Product	Office	Lasted
Jul 12, 3:34 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.1 hours before the alert went out and 181 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: 857 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 697 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 85 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.4

Open this sounding in Storm Lab

The text

As transmitted.

808 
WUUS51 KPHI 122108
SVRPHI
NJC005-007-021-PAC017-045-091-101-122215-
/O.NEW.KPHI.SV.W.0169.210712T2108Z-210712T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
508 PM EDT Mon Jul 12 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Camden County in southern New Jersey...
  Southern Mercer County in central New Jersey...
  Northwestern Burlington County in southern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Southeastern Bucks County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  East central Delaware County in southeastern Pennsylvania...

* Until 615 PM EDT.

* At 508 PM EDT, a severe thunderstorm was located over Andalusia, or
  10 miles northeast of Philadelphia, moving east at 15 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Trenton, Camden, Gloucester City, Cherry Hill,
  Bensalem, Mount Laurel, Ewing, Willingboro, Lumberton, Florence,
  Yeadon, Burlington, Bristol, Mount Holly, Riverside, Palmyra,
  Folcroft, Swarthmore and Hightstown.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 8.
 Pennsylvania Turnpike between mile markers 346 and 359.
 Interstate 95 in Pennsylvania between mile markers 15 and 40.
 Interstate 76 in Pennsylvania between mile markers 338 and 351.
 Interstate 76 in New Jersey between mile markers 2 and 3.
 Interstate 195 in New Jersey between mile markers 0 and 7.
 Interstate 295 in New Jersey between mile markers 34 and 66.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 0 and 4.
 Interstate 476 in Pennsylvania between mile markers 3 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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.

&&

LAT...LON 4018 7459 4018 7461 4017 7460 3989 7482
      3990 7540 4023 7499 4028 7452
TIME...MOT...LOC 2108Z 276DEG 12KT 4007 7496 

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

CMS

4 follow-up statements

517 
WWUS51 KPHI 122130
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
530 PM EDT Mon Jul 12 2021

NJC005-007-021-PAC017-045-091-101-122215-
/O.CON.KPHI.SV.W.0169.000000T0000Z-210712T2215Z/
Camden NJ-Mercer NJ-Burlington NJ-Montgomery PA-Bucks PA-
Philadelphia PA-Delaware PA-
530 PM EDT Mon Jul 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR NORTHWESTERN CAMDEN...SOUTHEASTERN MERCER...NORTHWESTERN
BURLINGTON...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN BUCKS...
PHILADELPHIA AND EAST CENTRAL DELAWARE COUNTIES...

At 529 PM EDT, a severe thunderstorm was located over Burlington, or
12 miles southwest of Trenton, moving east at 15 mph.

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

SOURCE...Law enforcement. Several reports of wires down have been 
         received near the Delaware River in Bucks and Burlington 
         Counties.

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

Locations impacted include...
Philadelphia, Trenton, Camden, Gloucester City, Cherry Hill,
Bensalem, Mount Laurel, Ewing, Willingboro, Lumberton, Florence,
Yeadon, Burlington, Bristol, Mount Holly, Riverside, Palmyra,
Folcroft, Swarthmore and Hightstown.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 8.
 Pennsylvania Turnpike between mile markers 349 and 359.
 Interstate 95 in Pennsylvania between mile markers 15 and 40.
 Interstate 76 in Pennsylvania between mile markers 339 and 351.
 Interstate 76 in New Jersey between mile markers 2 and 3.
 Interstate 195 in New Jersey between mile markers 0 and 7.
 Interstate 295 in New Jersey between mile markers 34 and 65.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 0 and 4.
 Interstate 476 in Pennsylvania between mile markers 3 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 4018 7459 4018 7461 4017 7460 3989 7482
      3990 7540 4024 7489 4028 7452
TIME...MOT...LOC 2129Z 276DEG 12KT 4006 7487 

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

CMS

269 
WWUS51 KPHI 122147
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
547 PM EDT Mon Jul 12 2021

NJC005-007-021-PAC017-045-091-101-122215-
/O.CON.KPHI.SV.W.0169.000000T0000Z-210712T2215Z/
Camden NJ-Mercer NJ-Burlington NJ-Montgomery PA-Bucks PA-
Philadelphia PA-Delaware PA-
547 PM EDT Mon Jul 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR NORTHWESTERN CAMDEN...SOUTHEASTERN MERCER...NORTHWESTERN
BURLINGTON...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN BUCKS...
PHILADELPHIA AND EAST CENTRAL DELAWARE COUNTIES...

At 547 PM EDT, a severe thunderstorm was located over Jacksonville,
or 11 miles south of Trenton, moving east at 15 mph.

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

SOURCE...Law enforcement.

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

Locations impacted include...
Philadelphia, Trenton, Camden, Gloucester City, Cherry Hill,
Bensalem, Mount Laurel, Ewing, Willingboro, Lumberton, Florence,
Yeadon, Burlington, Bristol, Mount Holly, Riverside, Palmyra,
Folcroft, Swarthmore and Hightstown.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 8.
 Pennsylvania Turnpike between mile markers 349 and 359.
 Interstate 95 in Pennsylvania between mile markers 15 and 40.
 Interstate 76 in Pennsylvania between mile markers 339 and 351.
 Interstate 76 in New Jersey between mile markers 2 and 3.
 Interstate 195 in New Jersey between mile markers 0 and 7.
 Interstate 295 in New Jersey between mile markers 34 and 65.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 0 and 4.
 Interstate 476 in Pennsylvania between mile markers 3 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 4018 7459 4018 7461 4017 7460 3989 7482
      3990 7540 4024 7489 4028 7452
TIME...MOT...LOC 2147Z 276DEG 12KT 4005 7479 

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

CMS

036 
WWUS51 KPHI 122200
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
600 PM EDT Mon Jul 12 2021

PAC091-122209-
/O.CAN.KPHI.SV.W.0169.000000T0000Z-210712T2215Z/
Montgomery PA-
600 PM EDT Mon Jul 12 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MONTGOMERY 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 1100 PM EDT for
southern and central New Jersey...and southeastern Pennsylvania.

LAT...LON 3989 7482 3990 7540 4006 7513 4005 7510
      4008 7509 4016 7495 4017 7461
TIME...MOT...LOC 2159Z 275DEG 11KT 4000 7497 

$$

NJC005-007-021-PAC017-045-101-122215-
/O.CON.KPHI.SV.W.0169.000000T0000Z-210712T2215Z/
Camden NJ-Mercer NJ-Burlington NJ-Bucks PA-Philadelphia PA-
Delaware PA-
600 PM EDT Mon Jul 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR NORTHWESTERN CAMDEN...SOUTH CENTRAL MERCER...NORTHWESTERN
BURLINGTON...SOUTHEASTERN BUCKS...PHILADELPHIA AND EAST CENTRAL
DELAWARE COUNTIES...

At 559 PM EDT, a severe thunderstorm was located over Riverside, or 8
miles northeast of Camden, moving east at 15 mph.

HAZARD...60 mph wind gusts.

SOURCE...Law enforcement.

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

Locations impacted include...
Philadelphia, Camden, Gloucester City, Cherry Hill, Bensalem, Mount
Laurel, Willingboro, Lumberton, Florence, Yeadon, Burlington,
Bristol, Mount Holly, Riverside, Palmyra, Folcroft, Swarthmore,
Bordentown, East Lansdowne and Beverly.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 7A.
 Pennsylvania Turnpike between mile markers 351 and 359.
 Interstate 95 in Pennsylvania between mile markers 15 and 40.
 Interstate 76 in Pennsylvania between mile markers 340 and 351.
 Interstate 76 in New Jersey between mile markers 2 and 3.
 Interstate 295 in New Jersey between mile markers 34 and 59.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 0 and 4.
 Interstate 476 in Pennsylvania near mile marker 3.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 3989 7482 3990 7540 4006 7513 4005 7510
      4008 7509 4016 7495 4017 7461
TIME...MOT...LOC 2159Z 275DEG 11KT 4000 7497 

HAIL...<.75IN
WIND...60MPH
 
$$

CMS

565 
WWUS51 KPHI 122216
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
616 PM EDT Mon Jul 12 2021

NJC005-007-021-PAC017-045-101-122225-
/O.EXP.KPHI.SV.W.0169.000000T0000Z-210712T2215Z/
Camden NJ-Mercer NJ-Burlington NJ-Bucks PA-Philadelphia PA-
Delaware PA-
616 PM EDT Mon Jul 12 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN CAMDEN...SOUTH
CENTRAL MERCER...NORTHWESTERN BURLINGTON...SOUTHEASTERN BUCKS...
PHILADELPHIA AND EAST CENTRAL DELAWARE COUNTIES HAS EXPIRED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been allowed to expire.  However, gusty 
winds and heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
southern and central New Jersey...and southeastern Pennsylvania.

LAT...LON 3989 7482 3990 7540 4006 7513 4005 7510
      4008 7509 4016 7495 4017 7461
TIME...MOT...LOC 2215Z 276DEG 12KT 3999 7490 

$$

CMS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 11, 10:21 PM EDT	Severe Thunderstorm Warning	PHI	Berks	24 min
Jul 11, 10:22 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	38 min
Jul 12, 1:59 PM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery, Philadelphia	3 hr
Jul 12, 2:12 PM EDT	Flash Flood Warning Emergency	PHI	Bucks, Philadelphia	7 hr
Jul 12, 2:28 PM EDT	Areal Flood Advisory	PHI	Chester	3 hr
Jul 12, 3:08 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Philadelphia	67 min
Jul 12, 4:16 PM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery, Philadelphia	114 min
Jul 12, 5:26 PM EDT	Areal Flood Advisory	PHI	Delaware, Montgomery, Philadelphia	2 hr
Jul 12, 5:41 PM EDT	Severe Thunderstorm Warning	PHI	Chester	34 min
Jul 12, 6:01 PM EDT	Flash Flood Warning	PHI	Philadelphia	102 min
Jul 12, 6:18 PM EDT	Flash Flood Warning	PHI	Delaware	84 min
Jul 12, 7:06 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	69 min
Jul 12, 2:20 PM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Monmouth	3 hr
Jul 12, 2:37 PM EDT	Flash Flood Warning	PHI	Mercer, Middlesex, Monmouth	93 min
Jul 12, 3:31 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth	41 min
Jul 12, 4:26 PM EDT	Special Marine Warning	PHI		2 hr
Jul 12, 4:33 PM EDT	Severe Thunderstorm Warning	PHI	Monmouth, Ocean	42 min
Jul 12, 4:52 PM EDT	Areal Flood Advisory	PHI	Monmouth, Ocean	98 min
Jul 12, 5:08 PM EDT	Areal Flood Advisory	PHI	Sussex	5 hr
Jul 12, 5:36 PM EDT	Special Weather Statement	PHI	Sussex	24 min
Jul 12, 5:41 PM EDT	Areal Flood Advisory	PHI	Burlington	83 min
Jul 12, 5:57 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Sussex	63 min
Jul 12, 6:08 PM EDT	Areal Flood Advisory	PHI	Morris	98 min
Jul 12, 6:43 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester	93 min
Jul 12, 6:52 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Sussex	34 min
Jul 12, 7:00 PM EDT	Areal Flood Advisory	PHI	Gloucester, Salem	112 min
Jul 12, 7:11 PM EDT	Flash Flood Warning	PHI	Morris, Sussex	35 min
Jul 12, 7:33 PM EDT	Special Marine Warning	PHI		58 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.