Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 16, NWS Philadelphia/Mount Holly

April 21, 20214 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 21, 2021, 2:17 PM EDT for 4 counties in New Jersey. It was in force for 43 min. 4 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 21, 2021, 2:17 PM EDT (18:17 UTC)
Expired
Apr 21, 2021, 3:00 PM EDT
In force
43 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Atlantic County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 71 km from the middle of the area, began a volume at 18:17 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 21, 2:20 PM EDTTSTM WND GST 541 W Millville Municipal, NJASOS STATION KMIV MILLVILLE.
Apr 21, 2:23 PM EDTHAIL 1Millville, NJ
Apr 21, 2:24 PM EDTHAIL 0.881 Wsw Millville, NJSOCIAL MEDIA. TIME ESTIMATED FROM RADAR.
Apr 21, 2:40 PM EDTHAIL 0.25Dorothy, NJ

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
Apr 21, 12:28 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 6.3 hours before the alert went out and 165 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, Wallops Is Stn, VA at 12:00Z on 2021-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 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, Wallops Is Stn, VA at 12:00Z on 2021-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 136 square meters per square second.1939587897Sfc1 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
12 J/kg
Mixed-layer CIN
-142 J/kg
Mixed-layer LCL
1437 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
136 m²/s²
0-3 km storm-relative helicity
126 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

239 
WUUS51 KPHI 211817
SVRPHI
NJC001-011-015-033-211900-
/O.NEW.KPHI.SV.W.0016.210421T1817Z-210421T1900Z/

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

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern Atlantic County in southern New Jersey...
  Central Cumberland County in southern New Jersey...
  Southeastern Salem County in southern New Jersey...
  Southeastern Gloucester County in southern New Jersey...

* Until 300 PM EDT.

* At 216 PM EDT, a severe thunderstorm was located over Fairton, or
  near Bridgeton, moving northeast at 40 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...
  Vineland, Millville, Bridgeton, Cumberland, Hammonton, Buena,
  Laurel Lake, Weymouth, Estell Manor, Newfield, Newport, Mays
  Landing, Dorothy, Fairton, Cedarville, Mizpah, South Vineland,
  Rosenhayn, Folsom and Collings Lakes.

This includes Atlantic City Expressway between mile markers 13 and
23.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3928 7522 3943 7531 3961 7483 3947 7459
      3933 7501 3932 7511
TIME...MOT...LOC 1816Z 244DEG 36KT 3938 7517 

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

JEO
3 follow-up statements
498 
WWUS51 KPHI 211828
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
228 PM EDT Wed Apr 21 2021

NJC001-011-015-033-211900-
/O.CON.KPHI.SV.W.0016.000000T0000Z-210421T1900Z/
Atlantic NJ-Cumberland NJ-Salem NJ-Gloucester NJ-
228 PM EDT Wed Apr 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR SOUTHWESTERN ATLANTIC...NORTHEASTERN CUMBERLAND...SOUTHEASTERN
SALEM AND SOUTHEASTERN GLOUCESTER COUNTIES...

At 227 PM EDT, a severe thunderstorm was located over South Vineland,
or over Vineland, moving northeast at 40 mph.

HAZARD...60 mph wind gusts and half dollar 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...
Vineland, Millville, Cumberland, Hammonton, Buena, Laurel Lake,
Weymouth, Estell Manor, Newfield, Mays Landing, Dorothy, Mizpah,
South Vineland, Rosenhayn, Folsom and Collings Lakes.

This includes Atlantic City Expressway between mile markers 13 and
23.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3947 7459 3933 7501 3933 7504 3948 7518
      3961 7483
TIME...MOT...LOC 1827Z 244DEG 36KT 3943 7503 

HAIL...1.25IN
WIND...60MPH
 
$$

JEO
355 
WWUS51 KPHI 211840
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
240 PM EDT Wed Apr 21 2021

NJC033-211850-
/O.CAN.KPHI.SV.W.0016.000000T0000Z-210421T1900Z/
Salem NJ-
240 PM EDT Wed Apr 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SALEM 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 600 PM EDT for
southern New Jersey.

LAT...LON 3947 7459 3938 7485 3954 7502 3961 7483
TIME...MOT...LOC 1840Z 244DEG 36KT 3949 7488 

$$

NJC001-011-015-211900-
/O.CON.KPHI.SV.W.0016.000000T0000Z-210421T1900Z/
Atlantic NJ-Cumberland NJ-Gloucester NJ-
240 PM EDT Wed Apr 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR SOUTHWESTERN ATLANTIC...NORTHEASTERN CUMBERLAND AND SOUTHEASTERN
GLOUCESTER COUNTIES...

At 240 PM EDT, a severe thunderstorm was located over Mizpah, or near
Vineland, moving northeast at 40 mph.

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

SOURCE...Public. Quarter size hail was reported in Millville.

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

Locations impacted include...
Vineland, Hammonton, Buena, Weymouth, Estell Manor, Newfield,
Dorothy, Mays Landing, Mizpah, Folsom and Collings Lakes.

This includes Atlantic City Expressway between mile markers 13 and
23.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 3947 7459 3938 7485 3954 7502 3961 7483
TIME...MOT...LOC 1840Z 244DEG 36KT 3949 7488 

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

JEO
176 
WWUS51 KPHI 211853
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
253 PM EDT Wed Apr 21 2021

NJC001-011-015-211902-
/O.EXP.KPHI.SV.W.0016.000000T0000Z-210421T1900Z/
Atlantic NJ-Cumberland NJ-Gloucester NJ-
253 PM EDT Wed Apr 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN ATLANTIC...
NORTHEASTERN CUMBERLAND AND SOUTHEASTERN GLOUCESTER COUNTIES WILL
EXPIRE AT 300 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 600 PM EDT for
southern New Jersey.

LAT...LON 3947 7459 3938 7485 3954 7502 3961 7483
TIME...MOT...LOC 1852Z 244DEG 36KT 3954 7476 

$$

JEO

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 8:48 PM EDTFreeze WatchPHIHunterdon, Morris, Somerset, Sussex, Warren7 hr
Apr 21, 3:26 AM EDTFreeze WarningPHIHunterdon, Morris, Somerset, Sussex, Warren30 hr
Apr 21, 12:25 PM EDTSevere Thunderstorm WarningPHIWarren50 min
Apr 21, 12:51 PM EDTSevere Thunderstorm WarningPHISussex, Warren21 min
Apr 21, 12:55 PM EDTSevere Thunderstorm WarningPHIHunterdon, Warren27 min
Apr 21, 1:10 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester, Mercer, Salem50 min
Apr 21, 1:17 PM EDTSpecial Weather StatementPHIHunterdon, Morris, Somerset, Sussex58 min
Apr 21, 1:28 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester36 min
Apr 21, 1:30 PM EDTSpecial Marine WarningPHI60 min
Apr 21, 1:43 PM EDTSevere Thunderstorm WarningPHIHunterdon, Middlesex, Morris, Somerset33 min
Apr 21, 1:58 PM EDTSpecial Weather StatementPHIBurlington, Camden, Monmouth, Ocean62 min
Apr 21, 2:02 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Monmouth, Ocean43 min
Apr 21, 2:03 PM EDTSpecial Weather StatementPHICumberland27 min
Apr 21, 2:28 PM EDTSpecial Weather StatementPHIMiddlesex, Monmouth47 min
Apr 21, 2:30 PM EDTSpecial Marine WarningPHI60 min
Apr 21, 2:38 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean37 min
Apr 21, 2:40 PM EDTSpecial Marine WarningPHI55 min
Apr 21, 2:43 PM EDTSpecial Weather StatementPHICape May32 min
Apr 21, 2:50 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Ocean40 min
Apr 21, 3:02 PM EDTSevere Thunderstorm WarningPHIAtlantic28 min
Apr 21, 3:07 PM EDTSpecial Marine WarningPHI53 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 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.