Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 194, NWS Philadelphia/Mount Holly

July 17, 20214 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 2021, 8:35 PM EDT for 4 counties in New Jersey. It was in force for 40 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 17, 2021, 8:35 PM EDT (00:35 UTC)
Expired
Jul 17, 2021, 9:15 PM EDT
In force
40 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ

The radar

The Philadelphia radar (KDIX), 47 km from the middle of the area, began a volume at 00:39 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 17, 1:13 PM EDTSevere Thunderstorm WatchSPC10 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.6 hours before the alert went out and 195 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 00:00Z on 2021-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1997 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 00:00Z on 2021-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 59 square meters per square second.1939Sfc1 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
1997 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1118 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
59 m²/s²
0-3 km storm-relative helicity
74 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

265 
WUUS51 KPHI 180035
SVRPHI
NJC001-005-007-015-180115-
/O.NEW.KPHI.SV.W.0194.210718T0035Z-210718T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
835 PM EDT Sat Jul 17 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Atlantic County in southern New Jersey...
  Southeastern Camden County in southern New Jersey...
  Eastern Gloucester County in southern New Jersey...
  Southeastern Burlington County in southern New Jersey...

* Until 915 PM EDT.

* At 834 PM EDT, severe thunderstorms were located along a line
  extending from near Hammonton to near Buena, moving northeast at 35
  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...
  Hammonton, Buena, Egg Harbor City, Weymouth, Port Republic, Wharton
  State Forest, Elwood-Magnolia, Wading River, Batsto, Mizpah, Penn
  State Forest, Folsom and Collings Lakes.

This includes the following highways...
 Garden State Parkway between mile markers 44 and 45.
 Atlantic City Expressway between mile markers 15 and 31.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3949 7452 3947 7493 3951 7497 3969 7485
      3973 7478 3980 7441
TIME...MOT...LOC 0034Z 235DEG 31KT 3969 7477 3951 7490 

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

JEO
2 follow-up statements
528 
WWUS51 KPHI 180051
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
851 PM EDT Sat Jul 17 2021

NJC007-015-180101-
/O.CAN.KPHI.SV.W.0194.000000T0000Z-210718T0115Z/
Camden NJ-Gloucester NJ-
851 PM EDT Sat Jul 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CAMDEN AND
EASTERN GLOUCESTER COUNTIES 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 1100 PM EDT for
southern New Jersey.

LAT...LON 3949 7452 3950 7488 3953 7488 3968 7479
      3971 7473 3980 7441
TIME...MOT...LOC 0051Z 235DEG 31KT 3977 7462 3959 7475 

$$

NJC001-005-180115-
/O.CON.KPHI.SV.W.0194.000000T0000Z-210718T0115Z/
Atlantic NJ-Burlington NJ-
851 PM EDT Sat Jul 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM EDT
FOR CENTRAL ATLANTIC AND SOUTHEASTERN BURLINGTON COUNTIES...

At 851 PM EDT, severe thunderstorms were located along a line
extending from near Wharton State Forest to near Elwood-Magnolia,
moving northeast at 35 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...
Hammonton, Egg Harbor City, Weymouth, Port Republic, Batsto, Wharton
State Forest, Elwood-Magnolia, Penn State Forest, Wading River and
Folsom.

This includes the following highways...
 Garden State Parkway between mile markers 44 and 45.
 Atlantic City Expressway between mile markers 16 and 27.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3949 7452 3950 7488 3953 7488 3968 7479
      3971 7473 3980 7441
TIME...MOT...LOC 0051Z 235DEG 31KT 3977 7462 3959 7475 

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

JEO
806 
WWUS51 KPHI 180107
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
907 PM EDT Sat Jul 17 2021

NJC001-005-180117-
/O.EXP.KPHI.SV.W.0194.000000T0000Z-210718T0115Z/
Atlantic NJ-Burlington NJ-
907 PM EDT Sat Jul 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL ATLANTIC AND
SOUTHEASTERN BURLINGTON COUNTIES WILL EXPIRE AT 915 PM EDT...
            
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 will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

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

LAT...LON 3949 7452 3950 7488 3953 7488 3968 7479
      3971 7473 3980 7441
TIME...MOT...LOC 0107Z 235DEG 31KT 3977 7462 3959 7475 

$$

JEO

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 8:00 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Mercer, Monmouth45 min
Jul 17, 8:09 PM EDTFlash Flood WarningPHIMercer, Somerset4 hr
Jul 17, 8:36 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean, Somerset54 min
Jul 17, 8:46 PM EDTSpecial Marine WarningPHI59 min
Jul 17, 8:53 PM EDTAreal Flood AdvisoryPHIMercer, Middlesex, Monmouth3 hr
Jul 17, 9:25 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester, Salem2 hr
Jul 17, 9:27 PM EDTSevere Thunderstorm WarningPHIGloucester, Salem48 min
Jul 17, 9:30 PM EDTSevere Thunderstorm WarningPHICape May29 min
Jul 17, 9:36 PM EDTFlash Flood WarningPHICamden, Gloucester, Salem2 hr
Jul 17, 9:44 PM EDTSpecial Marine WarningPHI61 min
Jul 17, 9:48 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester, Mercer, Salem42 min
Jul 17, 10:21 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean54 min
Jul 17, 10:22 PM EDTTornado WarningPHIBurlington, Monmouth, Ocean23 min
Jul 17, 10:27 PM EDTSpecial Weather StatementPHIBurlington, Camden33 min
Jul 17, 10:38 PM EDTTornado WarningPHIBurlington, Monmouth, Ocean16 min
Jul 17, 10:43 PM EDTFlash Flood WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean79 min
Jul 17, 10:47 PM EDTSpecial Marine WarningPHI118 min
Jul 17, 10:51 PM EDTSpecial Marine WarningPHI114 min
Jul 17, 11:07 PM EDTSpecial Weather StatementPHIMiddlesex38 min
Jul 17, 11:08 PM EDTAreal Flood WarningPHIHunterdon12 hr
Jul 17, 11:11 PM EDTSpecial Weather StatementPHIMonmouth, Ocean34 min
Jul 17, 11:20 PM EDTSpecial Marine WarningPHI115 min
Jul 17, 11:26 PM EDTAreal Flood WarningPHISomerset10 hr
Jul 18, 2:41 AM EDTAreal Flood WarningPHIMercer4 hr
Jul 18, 3:48 AM EDTRiver Flood WarningPHIMercer3 hr
Jul 18, 9:08 AM EDTAreal Flood WarningPHISomerset2 hr
Jul 18, 11:03 AM EDTRiver Flood WarningPHIMiddlesex, Somerset88 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.