Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 24, NWS Philadelphia/Mount Holly

April 29, 2021Bucks County, Philadelphia County, Pennsylvania; 5 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 29, 2021, 8:05 PM EDT for Bucks County, Philadelphia County, Pennsylvania; 5 counties in New Jersey. It was in force for 34 min. 5 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
Apr 29, 2021, 8:05 PM EDT (00:05 UTC)
Expired
Apr 29, 2021, 8:39 PM EDT
In force
34 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, Gloucester County, NJ, Monmouth County, NJ, Ocean County, NJ, Bucks County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 18 km from the middle of the area, began a volume at 00:09 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
Apr 29, 8:06 PM EDTTSTM WND DMGTacony, PAMPING REPORT OF SNAPPED OR UPROOTED TREES AT THIS LOCATION. TIME ESTIMATED FROM RADAR.
Apr 29, 8:10 PM EDTTSTM WND DMGCherry Hill, NJSEVERAL DOWNED TREES AND WIRES IN THE CHERRY HILL AREA. TIME ESTIMATED FROM RADAR.
Apr 29, 8:16 PM EDTTSTM WND DMG1 Sw Evesboro, NJSEVERAL REPORTS OF DOWNED WIRES IN THE GREENTREE AND MARLTON AREAS. TIME ESTIMATED FROM RADAR.
Apr 29, 8:17 PM EDTTSTM WND DMG3 N Mount Laurel, NJAN MPING REPORT OF LARGE TREE LIMBS OR POWER LINES DOWN. TIME ESTIMATED FROM RADAR.
Apr 29, 8:37 PM EDTTSTM WND GST 472 E Fort Dix, NJAWOS STATION KWRI MCGUIRE AFB.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 0.1 hours before the alert went out and 180 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 00:00Z on 2021-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2021-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 385 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
860 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
385 m²/s²
0-3 km storm-relative helicity
528 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

672 
WUUS51 KPHI 300005
SVRPHI
NJC005-007-015-025-029-PAC017-101-300100-
/O.NEW.KPHI.SV.W.0024.210430T0005Z-210430T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
805 PM EDT Thu Apr 29 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Ocean County in southern New Jersey...
  Northwestern Camden County in southern New Jersey...
  North central Gloucester County in southern New Jersey...
  Burlington County in southern New Jersey...
  Southwestern Monmouth County in central New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...
  East central Philadelphia County in southeastern Pennsylvania...

* Until 900 PM EDT.

* At 805 PM EDT, a severe thunderstorm was located over
  Erlton-Ellisburg, or near Gloucester City, moving east at 55 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Camden, Gloucester City, Cherry Hill, Jackson,
  Evesham, Mount Laurel, Willingboro, Voorhees, Medford, Lindenwold,
  Lumberton, Bellmawr, Burlington, Bristol, Mount Holly, Riverside,
  Berlin, Palmyra and Tabernacle.

People at the Burlington County Mega Site should seek safe shelter
immediately!

This includes the following highways...
 New Jersey Turnpike between exits 3 and 6A.
 Interstate 95 in Pennsylvania between mile markers 25 and 36.
 Interstate 76 in New Jersey between mile markers 0 and 2.
 Interstate 295 in New Jersey between mile markers 26 and 54.
 Interstate 676 in New Jersey near mile marker 0.
 Atlantic City Expressway near mile marker 44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3983 7426 3977 7512 4006 7510 4011 7475
      4014 7426
TIME...MOT...LOC 0005Z 265DEG 46KT 3990 7503 

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

Gorse
3 follow-up statements
381 
WWUS51 KPHI 300023
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
823 PM EDT Thu Apr 29 2021

NJC007-015-PAC017-101-300032-
/O.CAN.KPHI.SV.W.0024.000000T0000Z-210430T0100Z/
Camden NJ-Gloucester NJ-Bucks PA-Philadelphia PA-
823 PM EDT Thu Apr 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN CAMDEN...NORTH
CENTRAL GLOUCESTER...SOUTHEASTERN BUCKS AND EAST CENTRAL PHILADELPHIA
COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 3983 7426 3979 7490 3980 7491 4007 7491
      4010 7485 4011 7475 4014 7426
TIME...MOT...LOC 0022Z 255DEG 45KT 4010 7480 3998 7476 3983 7487 

$$

NJC005-025-029-300100-
/O.CON.KPHI.SV.W.0024.000000T0000Z-210430T0100Z/
Ocean NJ-Burlington NJ-Monmouth NJ-
823 PM EDT Thu Apr 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR NORTHWESTERN OCEAN...CENTRAL BURLINGTON AND SOUTHWESTERN MONMOUTH
COUNTIES...

At 822 PM EDT, severe thunderstorms were located along a line
extending from Florence to Mount Holly to Marlton Lakes, moving east
at 50 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Jackson, Evesham, Willingboro, Medford, Lumberton, Burlington,
Bristol, Mount Holly, Tabernacle, Presidential Lakes Estates,
Lakehurst, Pemberton, Wrightstown, Cedar Glen West, Leisuretowne,
Chatsworth, Jacksonville, Georgetown, Cassville and Presidential
Lakes.

This includes the following highways...
 New Jersey Turnpike between exits 5 and 6A.
 Interstate 295 in New Jersey between mile markers 41 and 54.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This line of severe thunderstorms may contain little or no 
lightning. Do not wait until you hear thunder before taking cover.

&&

LAT...LON 3983 7426 3979 7490 3980 7491 4007 7491
      4010 7485 4011 7475 4014 7426
TIME...MOT...LOC 0022Z 255DEG 45KT 4010 7480 3998 7476 3983 7487 

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

Gorse
643 
WWUS51 KPHI 300032
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
832 PM EDT Thu Apr 29 2021

NJC005-025-029-300100-
/O.CON.KPHI.SV.W.0024.000000T0000Z-210430T0100Z/
Ocean NJ-Burlington NJ-Monmouth NJ-
832 PM EDT Thu Apr 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR NORTHWESTERN OCEAN...NORTHEASTERN BURLINGTON AND SOUTHWESTERN
MONMOUTH COUNTIES...

At 832 PM EDT, severe thunderstorms were located along a line
extending from near Georgetown to near Wrightstown to near
Tabernacle, moving east at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Jackson, Tabernacle, Presidential Lakes Estates, Lakehurst,
Pemberton, Wrightstown, Cedar Glen West, Leisuretowne, Chatsworth,
Georgetown, Cassville, Presidential Lakes, Woodruff, Holiday
City-Berkeley, Bamber Lake, Cedar Glen Lakes, Whiting, Pine Ridge At
Crestwood, Browns Mills and Jobstown.

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

This line of severe thunderstorms may contain little or no 
lightning. Do not wait until you hear thunder before taking cover.

&&

LAT...LON 3983 7426 3980 7475 4011 7472 4014 7426
TIME...MOT...LOC 0032Z 265DEG 46KT 4011 7468 3999 7464 3984 7475 

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

Gorse
333 
WWUS51 KPHI 300039
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
839 PM EDT Thu Apr 29 2021

NJC005-025-029-300048-
/O.CAN.KPHI.SV.W.0024.000000T0000Z-210430T0100Z/
Ocean NJ-Burlington NJ-Monmouth NJ-
839 PM EDT Thu Apr 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN OCEAN...
NORTHEASTERN BURLINGTON AND SOUTHWESTERN MONMOUTH COUNTIES IS
CANCELLED...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning has been cancelled. However gusty winds are 
still possible with these thunderstorms.

LAT...LON 3983 7426 3980 7475 4011 7472 4014 7426
TIME...MOT...LOC 0037Z 265DEG 46KT 4012 7460 4000 7456 3985 7467 

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 29, 8:55 PM EDTSpecial Weather StatementPHIMonmouth35 min
Apr 30, 12:05 AM EDTStorm WarningPHI24 hr

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.