Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 302, NWS Philadelphia/Mount Holly

November 30, 2020New Castle County, Delaware; Chester County, Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 30, 2020, 2:41 PM EST for New Castle County, Delaware; Chester County, Delaware County, Pennsylvania. It was in force for 49 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, 2:41 PM EST (19:41 UTC)
Expired: Nov 30, 2020, 3:30 PM EST
In force: 49 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, Chester County, PA, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 113 km from the middle of the area, began a volume at 19:42 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
Nov 30, 3:07 PM EST	TSTM WND DMG	2 Nnw Nottingham Manor, DE	DOWNED TREES AND WIRES CLOSED WEDGEWOOD ROAD BETWEEN FOX LANE AND WALLACE DRIVE. TIME ESTIMATED FROM RADAR.
Nov 30, 3:15 PM EST	TSTM WND DMG	1 Se Downington, PA	WIRES DOWN AT THE INTERSECTION OF SKELP LEVEL RD AND SPENCER DR. TIME ESTIMATED FROM RADAR.
Nov 30, 3:15 PM EST	TSTM WND DMG	1 Sse Newlin Twp, PA	DOWNED TREE AND WIRES NEAR MARLBOROUGH ROAD IN MARLBORO. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM EST	TSTM WND DMG	1 E Downington, PA	DOWNED TREES AND WIRES NEAR LINCOLN AVENUE IN DOWNINGTOWN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM EST	TSTM WND DMG	1 E Marshallton, PA	DOWNED TREE AND WIRES NEAR LUCKY HILL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM EST	TSTM WND DMG	1 Ese Marshallton, PA	LARGE TREE DOWN ON LUCKY HILL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM EST	TSTM WND DMG	1 Wnw East Bradford Twp, PA	DOWNED TREES AND WIRES NEAR NORTH CREEK ROAD NEAR EAST BRADFORD TWP. TIME ESTIMATED FROM RADAR.
Nov 30, 3:19 PM EST	TSTM WND DMG	2 Wsw Pennsbury Twp, PA	DOWNED TREE ON ROUTE 1 NEAR STATE ROUTE 52. TIME ESTIMATED FROM RADAR.
Nov 30, 3:20 PM EST	TSTM WND DMG	2 Nne Winterthur, DE	DOWNED TREE ON MONTCHANIN ROAD NEAR TWADDELL MILL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:20 PM EST	TSTM WND DMG	2 Sw East Whiteland Twp, PA	WIRES DOWN NEAR FRAME AVE AND MULBERRY DR. TIME ESTIMATED FROM RADAR.
Nov 30, 3:20 PM EST	TSTM WND DMG	Pocopson Twp, PA	DOWNED TREE AND WIRES NEAR WILLIAMSBURG ROAD IN POCOPSON TWP. TIME ESTIMATED FROM RADAR.
Nov 30, 3:21 PM EST	TSTM WND DMG	1 E East Bradford Twp, PA	DOWNED TREE AND WIRES ON ASHBRIDGE STREET. TIME ESTIMATED FROM RADAR.
Nov 30, 3:21 PM EST	TSTM WND DMG	2 Wsw Brookfield, PA	WIRES DOWN NEAR THE INTERSECTION OF FAIRVILLE RD AND COSSART DR. TIME ESTIMATED FROM RADAR.
Nov 30, 3:22 PM EST	TSTM WND DMG	1 Nnw Pennsbury Twp, PA	WIRES DOWN NEAR THE INTERSECTION OF POCOPSON RD AND CHANDLER RD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:23 PM EST	TSTM WND DMG	1 Ene East Caln Twp, PA	TREE DOWN ON SHETLAND DRIVE. TIME ESTIMATED FROM RADAR.
Nov 30, 3:23 PM EST	TSTM WND DMG	2 Ese Exton, PA	DOWNED WIRES NEAR SHIP ROAD IN EXTON. TIME ESTIMATED FROM RADAR.
Nov 30, 3:23 PM EST	TSTM WND DMG	2 Nne Birmingham Twp, PA	DOWNED TREE NEAR THE INTERSECTION OF WILMINGTON PIKE AND WEST PLEASANT GROVE ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:25 PM EST	TSTM WND DMG	1 E West Whiteland Twp, PA	DOWNED WIRES NEAR EXTON SQUARE PARKWAY. TIME ESTIMATED FROM RADAR.
Nov 30, 3:26 PM EST	TSTM WND DMG	1 Wsw Malvern, PA	DOWNED TREE AND WIRES NEAR PICKWICK LANE IN MALVERN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:28 PM EST	TSTM WND DMG	1 Wnw Malvern, PA	DOWNED TREE AND WIRES NEAR WOODVIEW ROAD IN MALVERN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:28 PM EST	TSTM WND DMG	2 Ssw Malvern, PA	DOWNED TREE AND WIRES NEAR WOODLAND DRIVE IN MALVERN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:29 PM EST	TSTM WND DMG	2 W Schuylkill Twp, PA	DOWNED TREE AND WIRES NEAR HILLTOP ROAD IN CHARLESTOWN. TIME ESTIMATED FROM RADAR.
Nov 30, 3:33 PM EST	TSTM WND DMG	1 E Berwyn, PA	WIRES DOWN NEAR THE INTERSECTION OF WATERLOO RD AND HIGHLAND AVE. 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.

Issued	Product	Office	Lasted
Nov 30, 1:07 PM EST	Tornado Watch	SPC	6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.7 hours before the alert went out and 177 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: 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.

486 
WUUS51 KPHI 301941
SVRPHI
DEC003-PAC029-045-302030-
/O.NEW.KPHI.SV.W.0302.201130T1941Z-201130T2030Z/

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

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern New Castle County in northern Delaware...
  Chester County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 330 PM EST.

* At 241 PM EST, a severe thunderstorm was located over West
  Nottingham, or 7 miles north of Havre De Grace, moving northeast at
  55 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Wilmington, Newark, West Chester, Chester, Coatesville, Yeadon,
  Westtown, Downingtown, Swarthmore, Elsmere, Kennett Square, Oxford,
  Parkesburg, West Grove, East Lansdowne, Honey Brook, Elverson,
  Newport, Arden and Glen Roy.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 300 and 323.
 Interstate 95 in Pennsylvania between mile markers 0 and 8.
 Interstate 95 in Delaware between mile markers 13 and 23.
 Interstate 476 in Pennsylvania between mile markers 0 and 13.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3976 7606 3983 7604 3987 7599 3995 7600
      4004 7593 4011 7594 4021 7576 4003 7533
      3997 7528 3996 7525 3995 7525 3985 7533
      3974 7552 3966 7579 3972 7579 3972 7613
TIME...MOT...LOC 1941Z 216DEG 49KT 3965 7607 

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

JEO

3 follow-up statements

430 
WWUS51 KPHI 301959
SVSPHI

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

DEC003-PAC045-302008-
/O.CAN.KPHI.SV.W.0302.000000T0000Z-201130T2030Z/
New Castle DE-Delaware PA-
259 PM EST Mon Nov 30 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN NEW CASTLE AND
DELAWARE COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

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

LAT...LON 3976 7606 3981 7603 3983 7604 3983 7602
      3987 7599 3993 7600 3994 7598 3995 7600
      4004 7593 4011 7594 4021 7576 4009 7548
      3993 7569 3972 7578 3972 7613
TIME...MOT...LOC 1958Z 216DEG 49KT 3984 7589 

$$

PAC029-302030-
/O.CON.KPHI.SV.W.0302.000000T0000Z-201130T2030Z/
Chester PA-
259 PM EST Mon Nov 30 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EST
FOR CHESTER COUNTY...

At 258 PM EST, a severe thunderstorm was located near West Grove, or
13 miles northwest of Newark, moving northeast at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Coatesville, Downingtown, Oxford, Parkesburg, West Grove, Honey
Brook, Elverson, Homeville, Glen Roy, Cochranville, Pughtown, Mount
Vernon, Marshallton, Lionville-Marchwood, Glenmoore, Chester Springs,
Lionville, Ladenberg, Kemblesville and Atglen.

This includes Pennsylvania Turnpike between mile markers 300 and 321.
 
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...and southeastern Pennsylvania.

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

&&

LAT...LON 3976 7606 3981 7603 3983 7604 3983 7602
      3987 7599 3993 7600 3994 7598 3995 7600
      4004 7593 4011 7594 4021 7576 4009 7548
      3993 7569 3972 7578 3972 7613
TIME...MOT...LOC 1958Z 216DEG 49KT 3984 7589 

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

JEO

720 
WWUS51 KPHI 302013
SVSPHI

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

PAC029-302030-
/O.CON.KPHI.SV.W.0302.000000T0000Z-201130T2030Z/
Chester PA-
313 PM EST Mon Nov 30 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EST
FOR CENTRAL CHESTER COUNTY...

At 312 PM EST, a severe thunderstorm was located over Downingtown, or
7 miles northwest of West Chester, moving northeast at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Coatesville, Downingtown, Honey Brook, Elverson, Glenmoore, Chester
Springs, Pughtown, Lionville, Marshallton, Ladenberg,
Lionville-Marchwood, South Coatesville, Avondale, Modena, Exton,
Thorndale and Toughkenamon.

This includes Pennsylvania Turnpike between mile markers 300 and 321.
 
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...and southeastern Pennsylvania.

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

&&

LAT...LON 3991 7585 3999 7591 4004 7593 4011 7594
      4021 7576 4009 7548 3993 7569 3972 7578
TIME...MOT...LOC 2012Z 216DEG 49KT 4000 7574 

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

JEO

924 
WWUS51 KPHI 302024
SVSPHI

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

PAC029-302033-
/O.EXP.KPHI.SV.W.0302.000000T0000Z-201130T2030Z/
Chester PA-
324 PM EST Mon Nov 30 2020

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL CHESTER COUNTY WILL
EXPIRE AT 330 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...and southeastern Pennsylvania.

LAT...LON 3991 7585 3999 7591 4004 7593 4011 7594
      4021 7576 4009 7548 3993 7569 3972 7578
TIME...MOT...LOC 2023Z 216DEG 49KT 3966 7555 

$$

JEO

The office that day

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

Issued	Product	Office	Counties	Lasted
Nov 30, 11:35 AM EST	River Flood Warning	PHI	New Castle	11 hr
Nov 30, 12:15 PM EST	Areal Flood Advisory	PHI	New Castle	3 hr
Nov 30, 2:01 PM EST	Coastal Flood Statement	PHI	Sussex	3 hr
Nov 30, 2:48 PM EST	Areal Flood Warning	PHI	New Castle	8 hr
Nov 30, 3:01 PM EST	Severe Thunderstorm Warning	PHI	New Castle	44 min
Nov 30, 3:04 PM EST	Severe Thunderstorm Warning	PHI	Kent, New Castle	56 min
Nov 30, 3:21 PM EST	Tornado Warning Tornado observed	PHI	Kent	24 min
Nov 30, 3:47 PM EST	Tornado Warning	PHI	Kent	28 min
Nov 30, 5:24 PM EST	River Flood Warning	PHI	New Castle	5 hr
Nov 30, 5:39 PM EST	River Flood Warning	PHI	New Castle	4 hr
Nov 30, 12:41 PM EST	Special Weather Statement	PHI	Chester, Montgomery	49 min
Nov 30, 2:17 PM EST	Areal Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery	9 hr
Nov 30, 2:18 PM EST	Coastal Flood Advisory	PHI	Bucks, Delaware, Philadelphia	2 hr
Nov 30, 3:26 PM EST	Areal Flood Warning	PHI	Berks, Bucks, Carbon, Lehigh, Monroe, Northampton	4 hr
Nov 30, 3:43 PM EST	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Monroe, Montgomery, Northampton and 1 more	47 min
Nov 30, 3:51 PM EST	River Flood Warning	PHI	Chester	14 hr
Nov 30, 3:53 PM EST	Areal Flood Warning	PHI	Monroe, Northampton	16 hr
Nov 30, 3:53 PM EST	Tornado Warning	PHI	Bucks, Montgomery	13 min
Nov 30, 4:17 PM EST	Areal Flood Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	10 hr
Nov 30, 5:30 PM EST	River Flood Warning	PHI	Chester, Delaware	16 hr
Nov 30, 5:33 PM EST	River Flood Warning	PHI	Montgomery	10 hr
Nov 30, 5:35 PM EST	River Flood Warning	PHI	Delaware	4 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2020 Severe Thunderstorm Warnings in Delaware, 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.