Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 217, NWS Philadelphia/Mount Holly

July 21, 2021Bucks County, Pennsylvania; Burlington County, Camden County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2021, 3:48 PM EDT for Bucks County, Pennsylvania; Burlington County, Camden County, New Jersey. It was in force for 42 min. 3 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 21, 2021, 3:48 PM EDT (19:48 UTC)
Expired
Jul 21, 2021, 4:30 PM EDT
In force
42 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Burlington County, NJ, Camden County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 28 km from the middle of the area, began a volume at 19:51 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
Jul 21, 3:50 PM EDTTSTM WND DMG2 Ese New Albany, NJLARGE TREE LIMBS DOWN AND BLOCKING BRIDGEBORO ROAD NEAR THE WESTFIELD ROAD INTERSECTION IN MOORESTOWN. TIME ESTIMATED FROM RADAR.
Jul 21, 3:50 PM EDTHAIL 0.7Delanco, NJ
Jul 21, 3:51 PM EDTTSTM WND DMGDelanco, NJWIRES DOWN IN DELANCO NEAR BORDER WITH RIVERSIDE TOWNSHIP/RANCOCAS RIVER. 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.

IssuedProductOfficeLasted
Jul 21, 11:56 AM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.8 hours before the alert went out and 192 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 2021-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 130 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 2021-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 square meters per square second.193958Sfc1 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
130 J/kg
Mixed-layer CIN
-165 J/kg
Mixed-layer LCL
1495 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
48 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

045 
WUUS51 KPHI 211948
SVRPHI
NJC005-007-PAC017-212030-
/O.NEW.KPHI.SV.W.0217.210721T1948Z-210721T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
348 PM EDT Wed Jul 21 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Camden County in southern New Jersey...
  Burlington County in southern New Jersey...
  Southern Bucks County in southeastern Pennsylvania...

* Until 430 PM EDT.

* At 346 PM EDT, a cluster of severe thunderstorms were located 
  primarily over portions of Camden and Burlington counties, moving 
  east at 25mph, HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Minor damage to vehicles is possible. Wind damage to 
           roofs, siding, trees, and power lines is possible.

* Locations impacted include...
  Cherry Hill, Evesham, Mount Laurel, Willingboro, Voorhees, Medford,
  Lumberton, Florence, Burlington, Bristol, Mount Holly, Riverside,
  Berlin, Palmyra, Tabernacle, Shamong, Presidential Lakes Estates,
  Beverly, Chesilhurst and Pemberton.

This includes the following highways...
 New Jersey Turnpike between exits 4 and 6A.
 Pennsylvania Turnpike between mile markers 355 and 359.
 Interstate 95 in Pennsylvania between mile markers 35 and 40.
 Interstate 295 in New Jersey between mile markers 33 and 54.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

These storms have a history of producing widespread wind damage over 
the portions of SE PA.  

&&

LAT...LON 3973 7451 3970 7469 3973 7473 3971 7476
      3974 7489 3995 7507 4005 7497 4008 7496
      4014 7490 4008 7456 4006 7454 3997 7449
TIME...MOT...LOC 1947Z 290DEG 28KT 4004 7497 

HAIL...1.00IN
WIND...60MPH
 
$$

NC
2 follow-up statements
199 
WWUS51 KPHI 212011
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
411 PM EDT Wed Jul 21 2021

PAC017-212020-
/O.CAN.KPHI.SV.W.0217.000000T0000Z-210721T2030Z/
Bucks PA-
411 PM EDT Wed Jul 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN BUCKS 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 800 PM EDT for
southern New Jersey.

LAT...LON 3973 7451 3970 7469 3973 7473 3971 7476
      3983 7480 3990 7483 3996 7486 4002 7486
      4010 7478 4008 7456 4006 7454 3997 7449
TIME...MOT...LOC 2010Z 290DEG 28KT 3998 7474 

$$

NJC005-007-212030-
/O.CON.KPHI.SV.W.0217.000000T0000Z-210721T2030Z/
Camden NJ-Burlington NJ-
411 PM EDT Wed Jul 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR SOUTHEASTERN CAMDEN AND CENTRAL BURLINGTON COUNTIES...

At 410 PM EDT, a severe thunderstorm was located over Mount Holly, or
17 miles south of Trenton, moving east at 30 mph.

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

SOURCE...Radar indicated.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, 
         siding, trees, and power lines is possible.

Locations impacted include...
Medford, Lumberton, Mount Holly, Tabernacle, Shamong, Presidential
Lakes Estates, Pemberton, Wrightstown, Atsion, Leisuretowne,
Chatsworth, Jacksonville, Georgetown, Wharton State Forest,
Presidential Lakes, Browns Mills, Jobstown, Columbus, Medford Lakes
and Country Lake Estates.

This includes the following highways...
 New Jersey Turnpike between exits 5 and 6.
 Interstate 295 in New Jersey between mile markers 45 and 53.

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 3973 7451 3970 7469 3973 7473 3971 7476
      3983 7480 3990 7483 3996 7486 4002 7486
      4010 7478 4008 7456 4006 7454 3997 7449
TIME...MOT...LOC 2010Z 290DEG 28KT 3998 7474 

HAIL...1.00IN
WIND...60MPH
 
$$

NC
044 
WWUS51 KPHI 212022
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
422 PM EDT Wed Jul 21 2021

NJC005-007-212032-
/O.EXP.KPHI.SV.W.0217.000000T0000Z-210721T2030Z/
Camden NJ-Burlington NJ-
422 PM EDT Wed Jul 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CAMDEN AND
CENTRAL BURLINGTON COUNTIES WILL EXPIRE AT 430 PM EDT...
                
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 will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
southern New Jersey.

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 3973 7451 3970 7469 3973 7473 3971 7476
      3983 7480 3990 7483 3996 7486 4002 7486
      4010 7478 4008 7456 4006 7454 3997 7449
TIME...MOT...LOC 2022Z 290DEG 28KT 3995 7464 

$$

NC

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 1:08 PM EDTSpecial Weather StatementPHILehigh37 min
Jul 21, 1:11 PM EDTSpecial Weather StatementPHINorthampton34 min
Jul 21, 1:27 PM EDTSevere Thunderstorm WarningPHIBerks48 min
Jul 21, 2:03 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Northampton42 min
Jul 21, 2:14 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Delaware, Montgomery19 min
Jul 21, 2:41 PM EDTSpecial Weather StatementPHIMontgomery49 min
Jul 21, 2:48 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia42 min
Jul 21, 2:52 PM EDTSevere Thunderstorm WarningPHIChester, Delaware38 min
Jul 21, 3:16 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia44 min
Jul 21, 3:27 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Philadelphia33 min
Jul 21, 5:59 PM EDTSpecial Weather StatementPHIBerks31 min
Jul 21, 11:09 AM EDTSpecial Weather StatementPHIMorris36 min
Jul 21, 12:41 PM EDTSpecial Weather StatementPHIOcean34 min
Jul 21, 12:46 PM EDTSpecial Marine WarningPHI89 min
Jul 21, 12:51 PM EDTSevere Thunderstorm WarningPHIAtlantic, Ocean39 min
Jul 21, 12:53 PM EDTSevere Thunderstorm WarningPHIOcean67 min
Jul 21, 1:28 PM EDTSevere Thunderstorm WarningPHIAtlantic47 min
Jul 21, 1:43 PM EDTSevere Thunderstorm WarningPHIOcean49 min
Jul 21, 2:10 PM EDTSpecial Marine WarningPHI95 min
Jul 21, 2:13 PM EDTSevere Thunderstorm WarningPHIBurlington47 min
Jul 21, 2:35 PM EDTSpecial Marine WarningPHI55 min
Jul 21, 2:52 PM EDTSevere Thunderstorm WarningPHIOcean26 min
Jul 21, 3:04 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester56 min
Jul 21, 3:43 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean47 min
Jul 21, 3:48 PM EDTSpecial Marine WarningPHI57 min
Jul 21, 3:57 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester, Salem33 min
Jul 21, 4:04 PM EDTSpecial Marine WarningPHI56 min
Jul 21, 4:17 PM EDTSpecial Marine WarningPHI58 min
Jul 21, 4:50 PM EDTSpecial Marine WarningPHI55 min
Jul 21, 5:07 PM EDTSpecial Marine WarningPHI23 min
Jul 21, 5:09 PM EDTSpecial Marine WarningPHI66 min
Jul 21, 5:24 PM EDTSpecial Marine WarningPHI46 min
Jul 21, 5:31 PM EDTSevere Thunderstorm WarningPHICape May29 min
Jul 21, 5:52 PM EDTSpecial Marine WarningPHI53 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2021Severe Thunderstorm Warnings in Pennsylvania, 2021Every 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.