Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 303, NWS Philadelphia/Mount Holly

November 30, 2020New Castle County, Delaware; 4 counties in Pennsylvania; Gloucester County, Salem County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 30, 2020, 3:01 PM EST for New Castle County, Delaware; 4 counties in Pennsylvania; Gloucester County, Salem County, New Jersey. It was in force for 44 min. 23 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
Nov 30, 2020, 3:01 PM EST (20:01 UTC)
Expired
Nov 30, 2020, 3:45 PM EST
In force
44 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties New Castle County, DE, Gloucester County, NJ, Salem County, NJ, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 104 km from the middle of the area, began a volume at 20:02 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
Nov 30, 3:05 PM ESTTSTM WND DMG2 S Glasgow, DEDOWNED TREE LIMBS AT A RESIDENCE IN BEAR, CAUSING MINOR STRUCTURAL DAMAGE. TIME CONFIRMED BY RADAR.
Nov 30, 3:07 PM ESTTSTM WND DMG2 Nnw Nottingham Manor, DEDOWNED TREES AND WIRES CLOSED WEDGEWOOD ROAD BETWEEN FOX LANE AND WALLACE DRIVE. TIME ESTIMATED FROM RADAR.
Nov 30, 3:07 PM ESTTSTM WND DMG3 Sw Brookside, DEDOWNED TREES AND WIRES NEAR WELSH TRACT ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:15 PM ESTTSTM WND DMG1 Sse Newlin Twp, PADOWNED TREE AND WIRES NEAR MARLBOROUGH ROAD IN MARLBORO. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM ESTTSTM WND DMG1 E Marshallton, PADOWNED TREE AND WIRES NEAR LUCKY HILL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM ESTTSTM WND DMG1 Ese Marshallton, PALARGE TREE DOWN ON LUCKY HILL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM ESTTSTM WND DMG1 Wnw East Bradford Twp, PADOWNED TREES AND WIRES NEAR NORTH CREEK ROAD NEAR EAST BRADFORD TWP. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM ESTTSTM WND DMG2 Wsw Pennsbury Twp, PADOWNED TREE ON ROUTE 1 NEAR STATE ROUTE 52. TIME ESTIMATED FROM RADAR.
Nov 30, 3:20 PM ESTTSTM WND DMG2 Nne Winterthur, DEDOWNED TREE ON MONTCHANIN ROAD NEAR TWADDELL MILL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:20 PM ESTTSTM WND DMG2 Sw East Whiteland Twp, PAWIRES DOWN NEAR FRAME AVE AND MULBERRY DR. TIME ESTIMATED FROM RADAR.
Nov 30, 3:20 PM ESTTSTM WND DMGPocopson Twp, PADOWNED TREE AND WIRES NEAR WILLIAMSBURG ROAD IN POCOPSON TWP. TIME ESTIMATED FROM RADAR.
Nov 30, 3:21 PM ESTTSTM WND DMG1 E East Bradford Twp, PADOWNED TREE AND WIRES ON ASHBRIDGE STREET. TIME ESTIMATED FROM RADAR.
Nov 30, 3:21 PM ESTTSTM WND DMG2 Wsw Brookfield, PAWIRES DOWN NEAR THE INTERSECTION OF FAIRVILLE RD AND COSSART DR. TIME ESTIMATED FROM RADAR.
Nov 30, 3:22 PM ESTTSTM WND DMG1 Nnw Pennsbury Twp, PAWIRES DOWN NEAR THE INTERSECTION OF POCOPSON RD AND CHANDLER RD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:23 PM ESTTSTM WND DMG2 Ese Exton, PADOWNED WIRES NEAR SHIP ROAD IN EXTON. TIME ESTIMATED FROM RADAR.
Nov 30, 3:23 PM ESTTSTM WND DMG2 Nne Birmingham Twp, PADOWNED TREE NEAR THE INTERSECTION OF WILMINGTON PIKE AND WEST PLEASANT GROVE ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:26 PM ESTTSTM WND DMG1 Wsw Malvern, PADOWNED TREE AND WIRES NEAR PICKWICK LANE IN MALVERN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:28 PM ESTTSTM WND DMG1 Wnw Malvern, PADOWNED TREE AND WIRES NEAR WOODVIEW ROAD IN MALVERN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:28 PM ESTTSTM WND DMG2 Ssw Malvern, PADOWNED TREE AND WIRES NEAR WOODLAND DRIVE IN MALVERN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:33 PM ESTTSTM WND DMG1 E Berwyn, PAWIRES DOWN NEAR THE INTERSECTION OF WATERLOO RD AND HIGHLAND AVE. TIME ESTIMATED FROM RADAR.
Nov 30, 3:43 PM ESTTSTM WND DMG1 Sw South Chester, PADOWNED WIRES NEAR WILSON STREET IN SOUTH CHESTER. TIME ESTIMATED FROM RADAR.
Nov 30, 3:44 PM ESTTSTM WND DMG1 W Woodlyn, PADOWNED WIRES NEAR PLEASANT HILL ROAD IN GARDEN CITY. TIME ESTIMATED FROM RADAR.
Nov 30, 3:49 PM ESTTSTM WND DMG1 N Springfield Twp, PADOWNED TREE AND WIRES NEAR OVERHILL ROAD IN SPRINGFIELD TWP. 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
Nov 30, 1:07 PM ESTTornado WatchSPC6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.0 hours before the alert went out and 181 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, Washington/Dulle, VA at 12:00Z on 2020-11-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Washington/Dulle, VA at 12:00Z on 2020-11-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 384 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
498 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
384 m²/s²
0-3 km storm-relative helicity
623 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

768 
WUUS51 KPHI 302001
SVRPHI
DEC003-NJC015-033-PAC029-045-091-101-302045-
/O.NEW.KPHI.SV.W.0303.201130T2001Z-201130T2045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
301 PM EST Mon Nov 30 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  New Castle County in northern Delaware...
  Northwestern Salem County in southern New Jersey...
  Northwestern Gloucester County in southern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Southeastern Chester County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 345 PM EST.

* At 301 PM EST, a severe thunderstorm was located over Elkton,
  moving northeast at 70 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Camden, Wilmington, Newark, Middletown, West Chester,
  Norristown, Chester, West Norriton, East Norriton, Pennsville,
  Yeadon, Westtown, Carneys Point, Conshohocken, Folcroft, Ambler,
  Swarthmore, Elsmere and Paulsboro.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 320 and 340.
 Northeast Extension between mile markers 21 and 26.
 Interstate 95 in Pennsylvania between mile markers 0 and 15, and
between mile markers 20 and 29.
 Interstate 95 in Delaware between mile markers 0 and 23.
 Interstate 76 in Pennsylvania between mile markers 327 and 349.
 Interstate 295 in New Jersey between mile markers 0 and 14.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 476 in Pennsylvania between mile markers 0 and 19.

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.

A Tornado Watch remains in effect until 700 PM EST for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

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

&&

LAT...LON 3995 7569 4022 7537 4008 7496 3944 7576
      3945 7578 3972 7579 3972 7587
TIME...MOT...LOC 2001Z 223DEG 61KT 3961 7581 

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

JEO
2 follow-up statements
558 
WWUS51 KPHI 302028
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
328 PM EST Mon Nov 30 2020

DEC003-NJC015-033-PAC029-045-091-101-302045-
/O.CON.KPHI.SV.W.0303.000000T0000Z-201130T2045Z/
New Castle DE-Salem NJ-Gloucester NJ-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
328 PM EST Mon Nov 30 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 PM EST
FOR NORTHERN NEW CASTLE...NORTHWESTERN SALEM...NORTHWESTERN
GLOUCESTER...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN CHESTER...
PHILADELPHIA AND DELAWARE COUNTIES...

At 327 PM EST, a severe thunderstorm was located over Lima, or 10
miles east of West Chester, moving northeast at 70 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Philadelphia, Camden, Wilmington, Newark, Middletown, West Chester,
Norristown, Chester, West Norriton, East Norriton, Pennsville,
Yeadon, Westtown, Carneys Point, Conshohocken, Folcroft, Ambler,
Swarthmore, Elsmere and Paulsboro.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 320 and 340.
 Northeast Extension between mile markers 21 and 26.
 Interstate 95 in Pennsylvania between mile markers 0 and 15, and
between mile markers 20 and 29.
 Interstate 95 in Delaware between mile markers 1 and 23.
 Interstate 76 in Pennsylvania between mile markers 327 and 349.
 Interstate 295 in New Jersey between mile markers 0 and 14.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 476 in Pennsylvania between mile markers 0 and 19.

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.

A Tornado Watch remains in effect until 700 PM EST for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

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

&&

LAT...LON 3970 7577 3986 7565 3995 7569 4022 7537
      4008 7496 3944 7576 3945 7578
TIME...MOT...LOC 2027Z 223DEG 61KT 3994 7541 

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

JEO
164 
WWUS51 KPHI 302039
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
339 PM EST Mon Nov 30 2020

DEC003-NJC015-033-PAC029-045-091-101-302049-
/O.EXP.KPHI.SV.W.0303.000000T0000Z-201130T2045Z/
New Castle DE-Salem NJ-Gloucester NJ-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
339 PM EST Mon Nov 30 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN NEW CASTLE...
NORTHWESTERN SALEM...NORTHWESTERN GLOUCESTER...SOUTHEASTERN
MONTGOMERY...SOUTHEASTERN CHESTER...PHILADELPHIA AND DELAWARE
COUNTIES WILL EXPIRE AT 345 PM EST...
                
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 will be allowed to expire.  However gusty
winds are still possible with this thunderstorm.

A Tornado Watch remains in effect until 700 PM EST for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

LAT...LON 3970 7577 3986 7565 3995 7569 4022 7537
      4008 7496 3944 7576 3945 7578
TIME...MOT...LOC 2039Z 223DEG 61KT 3996 7539 

$$

JEO

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 30, 11:35 AM ESTRiver Flood WarningPHINew Castle11 hr
Nov 30, 12:15 PM ESTAreal Flood AdvisoryPHINew Castle3 hr
Nov 30, 2:01 PM ESTCoastal Flood StatementPHISussex3 hr
Nov 30, 2:41 PM ESTSevere Thunderstorm WarningPHINew Castle49 min
Nov 30, 2:48 PM ESTAreal Flood WarningPHINew Castle8 hr
Nov 30, 3:04 PM ESTSevere Thunderstorm WarningPHIKent, New Castle56 min
Nov 30, 3:21 PM ESTTornado Warning Tornado observedPHIKent24 min
Nov 30, 3:47 PM ESTTornado WarningPHIKent28 min
Nov 30, 5:24 PM ESTRiver Flood WarningPHINew Castle5 hr
Nov 30, 5:39 PM ESTRiver Flood WarningPHINew Castle4 hr
Nov 30, 12:41 PM ESTSpecial Weather StatementPHIChester, Montgomery49 min
Nov 30, 2:17 PM ESTAreal Flood WarningPHIBerks, Bucks, Lehigh, Montgomery9 hr
Nov 30, 2:18 PM ESTCoastal Flood AdvisoryPHIBucks, Delaware, Philadelphia2 hr
Nov 30, 3:26 PM ESTAreal Flood WarningPHIBerks, Bucks, Carbon, Lehigh, Monroe, Northampton4 hr
Nov 30, 3:43 PM ESTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Monroe, Montgomery, Northampton and 1 more47 min
Nov 30, 3:51 PM ESTRiver Flood WarningPHIChester14 hr
Nov 30, 3:53 PM ESTAreal Flood WarningPHIMonroe, Northampton16 hr
Nov 30, 3:53 PM ESTTornado WarningPHIBucks, Montgomery13 min
Nov 30, 4:17 PM ESTAreal Flood WarningPHIBucks, Delaware, Montgomery, Philadelphia10 hr
Nov 30, 5:30 PM ESTRiver Flood WarningPHIChester, Delaware16 hr
Nov 30, 5:33 PM ESTRiver Flood WarningPHIMontgomery10 hr
Nov 30, 5:35 PM ESTRiver Flood WarningPHIDelaware4 hr
Nov 30, 12:52 PM ESTAreal Flood AdvisoryPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 5 more92 min
Nov 30, 1:28 PM ESTAreal Flood AdvisoryPHIHunterdon, Warren2 hr
Nov 30, 2:01 PM ESTAreal Flood WarningPHIHunterdon, Mercer, Middlesex, Somerset9 hr
Nov 30, 2:34 PM ESTSpecial Weather StatementPHIMorris, Sussex56 min
Nov 30, 3:37 PM ESTSpecial Marine WarningPHI38 min
Nov 30, 3:58 PM ESTSmall Craft AdvisoryPHI56 hr
Nov 30, 4:49 PM ESTSevere Thunderstorm WarningPHICamden, Cumberland, Gloucester, Salem41 min
Nov 30, 5:05 PM ESTSpecial Marine WarningPHI40 min
Nov 30, 5:29 PM ESTSevere Thunderstorm WarningPHIMercer, Middlesex, Somerset46 min
Nov 30, 5:36 PM ESTRiver Flood WarningPHIHunterdon, Somerset7 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2020Severe Thunderstorm Warnings in New Jersey, 2020Severe Thunderstorm Warnings in Delaware, 2020Every 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.