Alert archive / New Jersey / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 279, NWS Philadelphia/Mount Holly

August 28, 20204 states

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 28, 2020, 4:39 PM EDT for 4 states. It was in force for 66 min. 9 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: Aug 28, 2020, 4:39 PM EDT (20:39 UTC)
Expired: Aug 28, 2020, 5:45 PM EDT
In force: 66 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Kent County, DE, New Castle County, DE, Cecil County, MD, Kent County, MD, Queen Anne's County, MD, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 92 km from the middle of the area, began a volume at 20:39 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.

What was reported inside it

Time	Report	Where	Remark
Aug 28, 4:39 PM EDT	TSTM WND DMG	1 W Lima, PA	A FEW REPORTS OF DOWNED TREES AND WIRES NEAR AND WEST OF LIMA. TIME ESTIMATED FROM RADAR.
Aug 28, 4:40 PM EDT	TSTM WND DMG	2 Ne Elkton, MD	TREES AND WIRES DOWN.
Aug 28, 4:42 PM EDT	TSTM WND DMG	1 W Stenton, PA	DOWNED POWER LINES NEAR SEDGLEY AVENUE. TIME ESTIMATED FROM RADAR.
Aug 28, 4:45 PM EDT	TSTM WND DMG	1 Ese Chester Heights, PA	A FEW REPORTS OF DOWNED TREES AND WIRES IN THE CHESTER HEIGHTS AND ASTON MILLS AREAS. TIME ESTIMATED FROM RADAR.
Aug 28, 4:50 PM EDT	HAIL 0.25	1 Ne Roxborough, PA
Aug 28, 5:05 PM EDT	TSTM WND GST 60	4 Ssw Elsinboro Twp, NJ	NJWXNET MEASURED 60 MPH WIND GUST AT LOWER ALLOWAYS CREEK.
Aug 28, 5:05 PM EDT	MARINE TSTM WIND 60	4 Ssw Elsinboro Twp, NJ	NJWXNET MEASURED 60 MPH WIND GUST AT LOWER ALLOWAYS CREEK.
Aug 28, 5:06 PM EDT	TSTM WND DMG	2 N Quinton, NJ	LARGE TREE DOWNED ON ACTON STATION ROAD. TIME ESTIMATED FROM RADAR.
Aug 28, 5:35 PM EDT	TSTM WND DMG	Cheswold, DE	SEVERAL REPORTS OF TREES AND WIRES DOWN IN THE VICINITY OF CHESWOLD. TIME ESTIMATED FROM RADAR AND POWER OUTAGE REPORTS.

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.

Issued	Product	Office	Lasted
Aug 28, 1:37 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.7 hours before the alert went out and 190 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 511 J/kg
Mixed-layer CIN: -119 J/kg
Mixed-layer LCL: 1109 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 50 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

543 
WUUS51 KPHI 282039
SVRPHI
DEC001-003-MDC015-029-035-NJC007-011-015-033-PAC045-091-101-282145-
/O.NEW.KPHI.SV.W.0279.200828T2039Z-200828T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
439 PM EDT Fri Aug 28 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  New Castle County in northern Delaware...
  Northwestern Kent County in central Delaware...
  Northeastern Queen Anne's County in northeastern Maryland...
  Northeastern Kent County in northeastern Maryland...
  Cecil County in northeastern Maryland...
  Northwestern Cumberland County in southern New Jersey...
  Salem County in southern New Jersey...
  Camden County in southern New Jersey...
  Gloucester County in southern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 545 PM EDT.

* At 437 PM EDT, severe thunderstorms were located along a line
  extending from Broomall to near Ashland to Newark to near Hollywood
  Beach, moving southeast at 35 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Camden, Wilmington, Vineland, Dover, Newark,
  Bridgeton, Middletown, Elkton, Gloucester City, Chester, Deptford,
  Voorhees, West Deptford, Glassboro, Lindenwold, Pennsville,
  Bellmawr, Yeadon and Woodbury.

This includes the following highways...
 New Jersey Turnpike between exits 1 and 3.
 Interstate 95 in Pennsylvania between mile markers 0 and 24, and
between mile markers 26 and 28, and near mile marker 32.
 Interstate 95 in Delaware between mile markers 0 and 23.
 Interstate 95 in Maryland between mile markers 97 and 109.
 Interstate 76 in Pennsylvania between mile markers 330 and 351.
 Interstate 76 in New Jersey between mile markers 0 and 3.
 Interstate 295 in New Jersey between mile markers 0 and 33.
 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 16.
 Atlantic City Expressway between mile markers 32 and 44.

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.

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with these storms. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

&&

LAT...LON 3973 7586 3972 7577 3981 7570 3984 7560
      3988 7559 3993 7554 3998 7544 4000 7545
      4008 7535 4006 7498 3997 7512 3985 7492
      3978 7489 3979 7483 3974 7475 3907 7567
      3943 7600 3952 7598 3955 7608
TIME...MOT...LOC 2037Z 317DEG 29KT 3998 7535 3982 7561 3970 7575 3953
7596

HAIL...0.75IN
WIND...60MPH
 
$$

Staarmann

2 follow-up statements

907 
WWUS51 KPHI 282110
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
510 PM EDT Fri Aug 28 2020

PAC091-101-282119-
/O.CAN.KPHI.SV.W.0279.000000T0000Z-200828T2145Z/
Montgomery PA-Philadelphia PA-
510 PM EDT Fri Aug 28 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MONTGOMERY AND
PHILADELPHIA 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 800 PM EDT for
central and northern Delaware...northeastern Maryland...southern New
Jersey...and southeastern Pennsylvania.

LAT...LON 3951 7576 3968 7550 3985 7533 3988 7527
      3987 7521 3988 7515 3995 7514 3996 7511
      3985 7492 3978 7489 3979 7483 3974 7475
      3907 7567 3918 7578 3937 7591
TIME...MOT...LOC 2109Z 316DEG 31KT 3979 7512 3961 7537 3945 7545 3934
7573

$$

DEC001-003-MDC015-029-035-NJC007-011-015-033-PAC045-282145-
/O.CON.KPHI.SV.W.0279.000000T0000Z-200828T2145Z/
New Castle DE-Kent DE-Queen Anne's MD-Kent MD-Cecil MD-Cumberland NJ-
Salem NJ-Camden NJ-Gloucester NJ-Delaware PA-
510 PM EDT Fri Aug 28 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM EDT
FOR SOUTHWESTERN NEW CASTLE...NORTHWESTERN KENT...NORTHEASTERN QUEEN
ANNE'S...NORTHEASTERN KENT...SOUTHEASTERN CECIL...NORTHWESTERN
CUMBERLAND...SALEM...CAMDEN...GLOUCESTER AND SOUTHEASTERN DELAWARE
COUNTIES...

At 509 PM EDT, severe thunderstorms were located along a line
extending from near Woodbury Heights to near Alloway to near Newport
Meadows to near Delaney Corner, moving southeast at 35 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Philadelphia, Camden, Vineland, Dover, Bridgeton, Middletown,
Gloucester City, Deptford, Voorhees, West Deptford, Glassboro,
Lindenwold, Pennsville, Bellmawr, Woodbury, Smyrna, Pitman, Carneys
Point, Berlin and Folcroft.

This includes the following highways...
 New Jersey Turnpike between exits 1 and 3.
 Interstate 95 in Pennsylvania near mile marker 11.
 Interstate 76 in New Jersey between mile markers 0 and 3.
 Interstate 295 in New Jersey between mile markers 1 and 33.
 Interstate 676 in New Jersey between mile markers 0 and 4.
 Atlantic City Expressway between mile markers 32 and 44.

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.

Frequent cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 3951 7576 3968 7550 3985 7533 3988 7527
      3987 7521 3988 7515 3995 7514 3996 7511
      3985 7492 3978 7489 3979 7483 3974 7475
      3907 7567 3918 7578 3937 7591
TIME...MOT...LOC 2109Z 316DEG 31KT 3979 7512 3961 7537 3945 7545 3934
7573

HAIL...0.75IN
WIND...60MPH
 
$$

Staarmann

320 
WWUS51 KPHI 282125
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
525 PM EDT Fri Aug 28 2020

MDC015-PAC045-282135-
/O.CAN.KPHI.SV.W.0279.000000T0000Z-200828T2145Z/
Cecil MD-Delaware PA-
525 PM EDT Fri Aug 28 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CECIL AND
SOUTHEASTERN DELAWARE 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 800 PM EDT for
central and northern Delaware...northeastern Maryland...and southern
New Jersey.

LAT...LON 3950 7551 3949 7534 3985 7509 3986 7493
      3978 7489 3979 7483 3974 7475 3911 7562
      3907 7567 3909 7569 3929 7585
TIME...MOT...LOC 2125Z 314DEG 32KT 3970 7499 3947 7513 3936 7534 3923
7571

$$

DEC001-003-MDC029-035-NJC007-011-015-033-282145-
/O.CON.KPHI.SV.W.0279.000000T0000Z-200828T2145Z/
New Castle DE-Kent DE-Queen Anne's MD-Kent MD-Cumberland NJ-Salem NJ-
Camden NJ-Gloucester NJ-
525 PM EDT Fri Aug 28 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM EDT
FOR SOUTHWESTERN NEW CASTLE...NORTHWESTERN KENT...NORTHEASTERN QUEEN
ANNE'S...EAST CENTRAL KENT...NORTHWESTERN CUMBERLAND...CENTRAL
SALEM...CENTRAL CAMDEN AND EASTERN GLOUCESTER COUNTIES...

At 525 PM EDT, severe thunderstorms were located along a line
extending from Williamstown to Rosenhayn to near Greenwich to near
Hartly, moving southeast at 35 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Vineland, Dover, Bridgeton, Voorhees, Glassboro, Lindenwold, Smyrna,
Pitman, Berlin, Magnolia, Clayton, Chesilhurst, Newfield, Elmer,
Cheswold, Greenwich, Shiloh, Hartly, Hazlettville and Newport
Meadows.

This includes Atlantic City Expressway between mile markers 32 and
44.
 
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.

Frequent cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 3950 7551 3949 7534 3985 7509 3986 7493
      3978 7489 3979 7483 3974 7475 3911 7562
      3907 7567 3909 7569 3929 7585
TIME...MOT...LOC 2125Z 314DEG 32KT 3970 7499 3947 7513 3936 7534 3923
7571

HAIL...0.75IN
WIND...60MPH
 
$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 1:53 PM EDT	Severe Thunderstorm Warning	PHI	Cecil, Kent	52 min
Aug 28, 2:40 PM EDT	Severe Thunderstorm Warning	PHI	Cecil, Kent	50 min
Aug 28, 4:01 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	44 min
Aug 28, 6:17 PM EDT	Severe Thunderstorm Warning	PHI	Caroline	43 min
Aug 27, 8:13 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Somerset, Warren	47 min
Aug 27, 8:24 PM EDT	Special Weather Statement	PHI	Middlesex, Somerset	51 min
Aug 27, 8:29 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	46 min
Aug 27, 8:55 PM EDT	Special Marine Warning	PHI		95 min
Aug 27, 9:13 PM EDT	Special Weather Statement	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	47 min
Aug 27, 9:28 PM EDT	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Monmouth, Ocean, Somerset	47 min
Aug 28, 3:05 PM EDT	Special Marine Warning	PHI		85 min
Aug 28, 3:41 PM EDT	Special Weather Statement	PHI	Salem	34 min
Aug 28, 3:52 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	53 min
Aug 28, 3:53 PM EDT	Special Marine Warning	PHI		67 min
Aug 28, 4:07 PM EDT	Special Marine Warning	PHI		53 min
Aug 28, 4:17 PM EDT	Severe Thunderstorm Warning	PHI	Cape May	43 min
Aug 28, 4:29 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Mercer	61 min
Aug 28, 4:49 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	56 min
Aug 28, 4:55 PM EDT	Special Marine Warning	PHI		95 min
Aug 28, 5:13 PM EDT	Special Marine Warning	PHI		92 min
Aug 28, 5:28 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more	47 min
Aug 28, 5:37 PM EDT	Special Marine Warning	PHI		83 min
Aug 28, 5:51 PM EDT	Special Marine Warning	PHI		84 min
Aug 28, 6:53 PM EDT	Special Marine Warning	PHI		64 min
Aug 28, 7:55 PM EDT	Special Marine Warning	PHI		65 min
Aug 27, 8:26 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Lehigh, Montgomery	26 min
Aug 28, 3:22 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Lehigh, Montgomery	53 min
Aug 28, 3:33 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Chester, Lehigh, Montgomery	101 min
Aug 28, 3:36 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester	54 min
Aug 28, 3:56 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	49 min
Aug 28, 3:15 PM EDT	Special Weather Statement	PHI	New Castle	30 min
Aug 28, 3:21 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	24 min
Aug 28, 5:40 PM EDT	Special Weather Statement	PHI	Kent	35 min
Aug 28, 7:53 PM EDT	Special Weather Statement	PHI	Sussex	37 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2020 Severe Thunderstorm Warnings in Maryland, 2020 Severe Thunderstorm Warnings in Pennsylvania, 2020 Every severe thunderstorm warning in 2020

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.