Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 198, NWS Philadelphia/Mount Holly

July 17, 2021Cape May County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 2021, 9:30 PM EDT for Cape May County, New Jersey. It was in force for 29 min. 1 report 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 17, 2021, 9:30 PM EDT (01:30 UTC)
Expired
Jul 17, 2021, 9:59 PM EDT
In force
29 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Cape May County, NJ

The radar

The Dover AFB radar (KDOX), 62 km from the middle of the area, began a volume at 01:31 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 17, 10:03 PM EDTHAIL 0.51 S Villas, NJREPORT FROM MPING: HALF-INCH (0.50 IN.).

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 17, 1:13 PM EDTSevere Thunderstorm WatchSPC10 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 1.5 hours before the alert went out and 143 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.

126 
WUUS51 KPHI 180130
SVRPHI
NJC009-180215-
/O.NEW.KPHI.SV.W.0198.210718T0130Z-210718T0215Z/

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

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Cape May County in southern New Jersey...

* Until 1015 PM EDT.

* At 930 PM EDT, a severe thunderstorm was located 8 miles northwest
  of North Cape May, or 11 miles northwest of Cape May, moving east
  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...
  Ocean City, Cape May, North Wildwood, Wildwood Crest, Woodbine, Sea
  Isle City, Avalon, West Cape May, Stone Harbor, Cape May Court
  House, Scotch Bonnet, Seaville, Diamond Beach, Green Creek,
  Dennisville, Goshen, Strathmere, Rio Grande, Eldora and North Cape
  May.

This includes Garden State Parkway between mile markers 0 and 24.
 
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 3926 7457 3912 7464 3892 7487 3892 7504
      3909 7498 3918 7493 3917 7492 3918 7491
      3920 7492 3923 7491
TIME...MOT...LOC 0130Z 250DEG 35KT 3903 7509 

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

JEO
1 follow-up statement
905 
WWUS51 KPHI 180159
SVSPHI

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

NJC009-180208-
/O.CAN.KPHI.SV.W.0198.000000T0000Z-210718T0215Z/
Cape May NJ-
959 PM EDT Sat Jul 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR CAPE MAY COUNTY IS
CANCELLED...
                
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 has been cancelled.

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

LAT...LON 3926 7457 3912 7464 3892 7487 3892 7504
      3909 7498 3918 7493 3917 7492 3918 7491
      3920 7492 3923 7491
TIME...MOT...LOC 0156Z 250DEG 35KT 3913 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, 8:35 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester40 min
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, 9:36 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.