Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 111, NWS Philadelphia/Mount Holly

July 1, 2021New Castle County, Delaware; 7 counties in New Jersey; 4 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 1, 2021, 4:27 PM EDT for New Castle County, Delaware; 7 counties in New Jersey; 4 counties in Pennsylvania. It was in force for 48 min. 6 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 1, 2021, 4:27 PM EDT (20:27 UTC)
Expired
Jul 1, 2021, 5:15 PM EDT
In force
48 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Salem County, NJ, Somerset County, NJ, Bucks County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 51 km from the middle of the area, began a volume at 20:29 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 1, 4:30 PM EDTTSTM WND DMG1 Ne Jenkintown, PADOWNED TREE ON WIRES NEAR THE INTERSECTION OF WASHINGTON LANE AND PEPPER ROAD. TIME ESTIMATED FROM RADAR.
Jul 1, 4:48 PM EDTTSTM WND DMGTacony, PAMPING REPORT OF WIND DAMAGE NEAR JACKSON STREET. TIME ESTIMATED FROM RADAR.
Jul 1, 4:50 PM EDTTSTM WND DMG1 Ne Feasterville-Trevo, PATREE DOWN ON U.S. ROUTE 1.
Jul 1, 4:53 PM EDTTSTM WND DMGLevittown, PASEVERAL REPORTS OF DOWNED TREE LIMBS AND WIRES IN LEVITTOWN. TIME ESTIMATED FROM RADAR.
Jul 1, 4:59 PM EDTTSTM WND DMG1 Se Fairless Hills, PASEVERAL REPORTS OF DOWNED POWER LINES NEAR FAIRLESS HILLS. TIME ESTIMATED FROM RADAR.
Jul 1, 5:19 PM EDTTSTM WND DMG2 Wsw Yardville, NJDOWNED WIRES ON GRAND AVENUE. 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 1, 12:46 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 8.5 hours before the alert went out and 197 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 2021-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 286 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 2021-07-01The 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
286 J/kg
Mixed-layer CIN
-126 J/kg
Mixed-layer LCL
978 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
84 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

032 
WUUS51 KPHI 012027
SVRPHI
DEC003-NJC005-007-015-019-021-033-035-PAC017-045-091-101-012115-
/O.NEW.KPHI.SV.W.0111.210701T2027Z-210701T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
427 PM EDT Thu Jul 1 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northeastern New Castle County in northern Delaware...
  Northern Salem County in southern New Jersey...
  South central Hunterdon County in northwestern New Jersey...
  Northwestern Camden County in southern New Jersey...
  Mercer County in central New Jersey...
  Northwestern Gloucester County in southern New Jersey...
  Northwestern Burlington County in southern New Jersey...
  South central Somerset County in northern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Southeastern Bucks County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 515 PM EDT.

* At 426 PM EDT, severe thunderstorms were located along a line
  extending from New Hope to Bryn Athyn to near Newtown Square to
  Delaware City, moving east at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Law enforcement.

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

* Locations impacted include...
  Philadelphia, Trenton, Camden, Wilmington, Gloucester City,
  Bensalem, Ewing, Chester, Willingboro, Deptford, West Deptford,
  Glassboro, Pennsville, Princeton, Florence, Bellmawr, Yeadon,
  Woodbury, Burlington and Bristol.

People at the Welcome America Events should seek safe shelter
immediately!

This includes the following highways...
 New Jersey Turnpike between exits 1 and 3, and between exits 6 and
6A.
 Pennsylvania Turnpike between mile markers 341 and 359.
 Interstate 95 in Pennsylvania between mile markers 0 and 40.
 Interstate 95 in Delaware between mile markers 11 and 23.
 Interstate 76 in Pennsylvania between mile markers 335 and 351.
 Interstate 76 in New Jersey between mile markers 0 and 3.
 Interstate 195 in New Jersey between mile markers 0 and 3.
 Interstate 295 in New Jersey between mile markers 0 and 30, and
between mile markers 55 and 76.
 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 0 and 11.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4035 7463 4033 7462 4014 7468 3997 7498
      3957 7522 3957 7569 3994 7547 4013 7516
      4040 7503 4041 7460
TIME...MOT...LOC 2026Z 266DEG 24KT 4037 7498 4014 7509 3995 7540 3960
7559

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

CMS
1 follow-up statement
131 
WWUS51 KPHI 012049
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
449 PM EDT Thu Jul 1 2021

DEC003-012058-
/O.CAN.KPHI.SV.W.0111.000000T0000Z-210701T2115Z/
New Castle DE-
449 PM EDT Thu Jul 1 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN NEW CASTLE COUNTY
IS CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northern Delaware...southern, central and northern New Jersey...and
southeastern Pennsylvania.

LAT...LON 4014 7468 3997 7498 3957 7522 3957 7550
      4004 7531 4013 7516 4040 7492 4041 7460
TIME...MOT...LOC 2048Z 266DEG 24KT 4038 7479 4015 7490 3996 7521 3961
7540

$$

NJC005-007-015-019-021-033-035-PAC017-045-091-101-012115-
/O.CON.KPHI.SV.W.0111.000000T0000Z-210701T2115Z/
Salem NJ-Hunterdon NJ-Camden NJ-Mercer NJ-Gloucester NJ-
Burlington NJ-Somerset NJ-Montgomery PA-Bucks PA-Philadelphia PA-
Delaware PA-
449 PM EDT Thu Jul 1 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR CENTRAL SALEM...SOUTHERN HUNTERDON...NORTHWESTERN CAMDEN...
MERCER...NORTHWESTERN GLOUCESTER...NORTHWESTERN BURLINGTON...SOUTH
CENTRAL SOMERSET...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN BUCKS...
PHILADELPHIA AND EASTERN DELAWARE COUNTIES...

At 448 PM EDT, severe thunderstorms were located along a line
extending from Hopewell to near Langhorn to near Roxborough to near
Alloway, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Philadelphia, Trenton, Camden, Gloucester City, Bensalem, Ewing,
Chester, Willingboro, Deptford, West Deptford, Glassboro, Princeton,
Florence, Bellmawr, Yeadon, Woodbury, Burlington, Bristol, Pitman and
Riverside.

People at the Welcome America Events should seek safe shelter
immediately!

This includes the following highways...
 New Jersey Turnpike between exits 1 and 3, and between exits 6 and
6A.
 Pennsylvania Turnpike between mile markers 342 and 359.
 Interstate 95 in Pennsylvania between mile markers 4 and 40.
 Interstate 76 in Pennsylvania between mile markers 335 and 351.
 Interstate 76 in New Jersey between mile markers 0 and 3.
 Interstate 195 in New Jersey between mile markers 0 and 3.
 Interstate 295 in New Jersey between mile markers 5 and 30, and
between mile markers 55 and 76.
 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 0 and 3, and
between mile markers 6 and 8.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4014 7468 3997 7498 3957 7522 3957 7550
      4004 7531 4013 7516 4040 7492 4041 7460
TIME...MOT...LOC 2048Z 266DEG 24KT 4038 7479 4015 7490 3996 7521 3961
7540

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

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 9:21 PM EDTSpecial Weather StatementPHINew Castle39 min
Jul 1, 3:48 PM EDTAreal Flood AdvisoryPHINew Castle112 min
Jul 1, 3:50 PM EDTSevere Thunderstorm WarningPHINew Castle40 min
Jul 1, 4:08 PM EDTSevere Thunderstorm WarningPHISussex52 min
Jul 1, 4:08 PM EDTSevere Thunderstorm WarningPHIKent52 min
Jul 1, 4:10 PM EDTAreal Flood AdvisoryPHIKent, New Castle94 min
Jul 1, 4:32 PM EDTSevere Thunderstorm WarningPHIKent, New Castle, Sussex43 min
Jul 1, 4:57 PM EDTTornado WarningPHIKent, Sussex22 min
Jul 1, 5:12 PM EDTSevere Thunderstorm WarningPHIKent, Sussex48 min
Jun 30, 8:37 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer38 min
Jun 30, 8:56 PM EDTSpecial Marine WarningPHI94 min
Jun 30, 9:05 PM EDTSpecial Weather StatementPHISomerset40 min
Jun 30, 9:49 PM EDTSpecial Weather StatementPHIMonmouth26 min
Jun 30, 9:51 PM EDTSpecial Marine WarningPHI60 min
Jul 1, 2:58 AM EDTSmall Craft AdvisoryPHI17 hr
Jul 1, 1:10 PM EDTSpecial Weather StatementPHIMonmouth50 min
Jul 1, 1:16 PM EDTSpecial Weather StatementPHIAtlantic29 min
Jul 1, 1:28 PM EDTSpecial Marine WarningPHI62 min
Jul 1, 1:31 PM EDTSpecial Weather StatementPHICumberland29 min
Jul 1, 4:21 PM EDTSpecial Marine WarningPHI114 min
Jul 1, 4:55 PM EDTSevere Thunderstorm WarningPHICape May, Cumberland, Salem80 min
Jul 1, 4:59 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester, Mercer, Middlesex, Monmouth and 2 more46 min
Jul 1, 5:02 PM EDTTornado WarningPHIBurlington, Mercer28 min
Jul 1, 5:27 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 5 more93 min
Jul 1, 5:35 PM EDTTornado WarningPHIMercer, Monmouth, Ocean25 min
Jul 1, 5:40 PM EDTSpecial Marine WarningPHI65 min
Jul 1, 5:46 PM EDTSpecial Marine WarningPHI119 min
Jul 1, 6:13 PM EDTSpecial Marine WarningPHI92 min
Jun 30, 8:16 PM EDTSpecial Weather StatementPHIBucks, Montgomery44 min
Jul 1, 2:51 PM EDTSpecial Weather StatementPHIChester, Montgomery39 min
Jul 1, 3:13 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery47 min
Jul 1, 3:23 PM EDTAreal Flood AdvisoryPHIChester, Montgomery77 min

Nearby

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