Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 305, NWS Philadelphia/Mount Holly

November 30, 2020Hunterdon County, Warren County, New Jersey; 7 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 30, 2020, 3:43 PM EST for Hunterdon County, Warren County, New Jersey; 7 counties in Pennsylvania. It was in force for 47 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, 3:43 PM EST (20:43 UTC)
Expired: Nov 30, 2020, 4:30 PM EST
In force: 47 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Hunterdon County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 95 km from the middle of the area, began a volume at 20:44 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, 3:44 PM EST	TSTM WND DMG	1 Nnw Skippack Twp, PA	DOWNED TREES AND WIRES NEAR TYSON ROAD IN SKIPPACK TWP. TIME ESTIMATED FROM RADAR.
Nov 30, 3:44 PM EST	TSTM WND DMG	1 S Harleysville, PA	DOWNED TREES AND WIRES NEAR OLD MORRIS ROAD IN LEDERACH. TIME ESTIMATED FROM RADAR.
Nov 30, 3:44 PM EST	TSTM WND DMG	2 Ssw Glendon, PA	DOWNED TREES AND WIRES NEAR GAFFNEY HILL ROAD AND TEXAS ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:46 PM EST	TSTM WND DMG	Harleysville, PA	DOWNED TREES AND WIRES NEAR MAPLE AVENUE IN HARLEYSVILLE. TIME ESTIMATED FROM RADAR.
Nov 30, 3:46 PM EST	TSTM WND DMG	North Wales, PA	CORRECTS PREVIOUS TSTM WND DMG REPORT FROM NORTH WALES. DRONE FOOTAGE SHOWING DAMAGE TO WHAT APPEARS TO BE A COUPLE HOTELS AND CARS SHIFTED AROUND IN A PARKING LOT. TIME ESTIMATED FROM RADAR.
Nov 30, 3:47 PM EST	TSTM WND DMG	2 Ene Marlborough Twp, PA	DOWNED TREE ON SWAMP CREEK ROAD NEAR THE PRICE ROAD INTERSECTION. ROAD WAS CLOSED. TIME ESTIMATED FROM RADAR.
Nov 30, 3:47 PM EST	TSTM WND DMG	Upper Milford Twp, PA	DOWNED TREE IN WIRES NEAR OAK LANE IN UPPER MILFORD TWP. TIME ESTIMATED FROM RADAR.
Nov 30, 3:47 PM EST	TORNADO	1 Sse Montgomeryville, PA	AN EF-0 TORNADO TOUCHED DOWN IMMEDIATELY EAST OF THE ROUTE 309 (BETHLEHEM PIKE) NORTHBOUND ONRAMP TO THE 202 PARKWAY IN MONTGOMERYVILLE, PA AROUND 347 PM. AS THE TORNADO CROSSED THE PARKWAY, TWO SMALL TREES WERE UPROOTED ON ITS NORTHBOUND SIDE. OUTDOOR WOODEN
Nov 30, 3:47 PM EST	TORNADO	1 Sse Montgomeryville, PA	AN EF-0 TORNADO TOUCHED DOWN IMMEDIATELY EAST OF THE ROUTE 309 (BETHLEHEM PIKE) NORTHBOUND ONRAMP TO THE 202 PARKWAY IN MONTGOMERYVILLE, PA AROUND 347 PM. AS THE TORNADO CROSSED THE PARKWAY, TWO SMALL TREES WERE UPROOTED ON ITS NORTHBOUND SIDE. OUTDOOR WOODEN
Nov 30, 3:47 PM EST	TORNADO	1 Sse Montgomeryville, PA	AN EF-0 TORNADO TOUCHED DOWN IMMEDIATELY EAST OF THE ROUTE 309 (BETHLEHEM PIKE) NORTHBOUND ONRAMP TO THE 202 PARKWAY IN MONTGOMERYVILLE, PA AROUND 347 PM. AS THE TORNADO CROSSED THE PARKWAY, TWO SMALL TREES WERE UPROOTED ON ITS NORTHBOUND SIDE. OUTDOOR WOODEN
Nov 30, 3:47 PM EST	TORNADO	1 Sse Montgomeryville, PA	AN EF-0 TORNADO TOUCHED DOWN IMMEDIATELY EAST OF THE ROUTE 309 (BETHLEHEM PIKE) NORTHBOUND ONRAMP TO THE 202 PARKWAY IN MONTGOMERYVILLE, PA AROUND 347 PM. AS THE TORNADO CROSSED THE PARKWAY, TWO SMALL TREES WERE UPROOTED ON ITS NORTHBOUND SIDE. OUTDOOR WOODEN
Nov 30, 3:49 PM EST	TSTM WND DMG	1 Nne Wilson, PA	DOWNED TREE IN WIRES NEAR THE INTERSECTION OF WOOD AVENUE AND HACKETT AVENUE. TIME ESTIMATED FROM RADAR.
Nov 30, 3:53 PM EST	TSTM WND DMG	1 Ssw Haycock Twp, PA	DOWNED TREE IN WIRES NEAR ROUDENBUSH ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 3:55 PM EST	TSTM WND DMG	1 Se Montgomeryville, PA	DOWNED TREE NEAR THE DUCHESS PLACE AND CATHEDRAL DRIVE INTERSECTION. TIME ESTIMATED FROM RADAR.
Nov 30, 3:55 PM EST	TSTM WND DMG	1 Se Montgomeryville, PA	CONSIDERABLE DAMAGE OBSERVED AROUND THE COSTCO IN NORTH WALES/MONTGOMERYVILLE PA REPORTED FROM MULTIPLE SOURCES (POSSIBLE TORNADO). TIME ESTIMATED FROM RADAR.
Nov 30, 3:55 PM EST	TSTM WND DMG	1 Sse Chalfont, PA	DOWNED TREES AND WIRES NEAR BLACKBURN DRIVE IN CHALFONT. TIME ESTIMATED FROM RADAR.
Nov 30, 3:59 PM EST	TSTM WND DMG	1 Nnw Horsham Twp, PA	DOWNED UTILITY ON LIMEKILN PIKE NEAR FAIRWAY ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 4:06 PM EST	TSTM WND DMG	2 Nnw Warminster, PA	DOWNED TREE AND WIRES NEAR SINKLER ROAD IN NESHAMINY. TIME ESTIMATED FROM RADAR.
Nov 30, 4:08 PM EST	TSTM WND DMG	Swinesburg, NJ	DOWNED TREES AND WIRES NEAR TURKEY HILL ROAD AND BLOOMSBURY ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 4:10 PM EST	TSTM WND DMG	2 Ne Doylestown, PA	DOWNED TREES AND WIRES NEAR CHURCH SCHOOL ROAD AND FELL ROAD IN DOYLESTOWN. TIME ESTIMATED FROM RADAR.
Nov 30, 4:12 PM EST	TSTM WND DMG	Chalfont, PA	FENCE AND TREE KNOCKED DOWN IN CHALFONT, PA. TIME ESTIMATED BY RADAR.
Nov 30, 4:13 PM EST	TSTM WND DMG	Asbury, NJ	DOWNED TREES AND WIRES NEAR LUDLOW STATION ROAD AND ASBURY WEST PORTAL ROAD. TIME ESTIMATED FROM RADAR.
Nov 30, 4:15 PM EST	TSTM WND DMG	2 Nnw Holicong, PA	DOWNED TREES AND WIRES NEAR MECHANICSVILLE ROAD. 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

Brookhaven, NY (KOKX), 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 958 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 306 m²/s²
0-3 km storm-relative helicity: 408 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

390 
WUUS51 KPHI 302043
SVRPHI
NJC019-041-PAC011-017-077-089-091-095-101-302130-
/O.NEW.KPHI.SV.W.0305.201130T2043Z-201130T2130Z/

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

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Hunterdon County in northwestern New Jersey...
  Southwestern Warren County in northwestern New Jersey...
  Eastern Berks County in eastern Pennsylvania...
  Southeastern Lehigh County in eastern Pennsylvania...
  Central Montgomery County in southeastern Pennsylvania...
  Bucks County in southeastern Pennsylvania...
  Northwestern Philadelphia County in southeastern Pennsylvania...
  South central Monroe County in northeastern Pennsylvania...
  Northampton County in eastern Pennsylvania...

* Until 430 PM EST.

* At 343 PM EST, severe thunderstorms were located along a line
  extending from near Zionsville to Ambler, moving north 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, Allentown, Easton, Bethlehem, Lansdale, Forks, East
  Norriton, Emmaus, Northampton, Quakertown, Perkasie, Doylestown,
  Byram, Wilson, Hatboro, Souderton, Bedminster, Washington, Ambler
  and Hellertown.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 334 and 342.
 Northeast Extension between mile markers 21 and 57.
 Interstate 78 in Pennsylvania between mile markers 54 and 76.
 Interstate 78 in New Jersey between mile markers 0 and 23.
 Interstate 80 in Pennsylvania between mile markers 305 and 310.

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 northwestern
New Jersey...and southeastern Pennsylvania.

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

&&

LAT...LON 4074 7483 4071 7475 4003 7521 4047 7565
      4103 7528
TIME...MOT...LOC 2043Z 197DEG 62KT 4048 7557 4016 7525 

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

JEO

2 follow-up statements

539 
WWUS51 KPHI 302108
SVSPHI

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

PAC011-089-302118-
/O.CAN.KPHI.SV.W.0305.000000T0000Z-201130T2130Z/
Berks PA-Monroe PA-
408 PM EST Mon Nov 30 2020

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN BERKS AND SOUTH
CENTRAL MONROE COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

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

LAT...LON 4075 7486 4071 7475 4003 7521 4053 7532
      4060 7552 4089 7526 4090 7523 4091 7524
      4093 7522 4094 7518 4095 7517 4095 7515
TIME...MOT...LOC 2108Z 197DEG 62KT 4088 7541 4056 7509 

$$

NJC019-041-PAC017-077-091-095-101-302130-
/O.CON.KPHI.SV.W.0305.000000T0000Z-201130T2130Z/
Hunterdon NJ-Warren NJ-Lehigh PA-Montgomery PA-Bucks PA-
Philadelphia PA-Northampton PA-
408 PM EST Mon Nov 30 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EST
FOR HUNTERDON...SOUTHWESTERN WARREN...EAST CENTRAL LEHIGH...
SOUTHEASTERN MONTGOMERY...CENTRAL BUCKS...NORTHWESTERN PHILADELPHIA
AND NORTHAMPTON COUNTIES...

At 408 PM EST, severe thunderstorms were located along a line
extending from Rossland to Milford, moving north 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, Allentown, Easton, Bethlehem, Forks, Perkasie,
Doylestown, Byram, Wilson, Hatboro, Bedminster, Washington, Ambler,
Hellertown, Nazareth, Bangor, Chalfont, Tinicum, High Bridge and Pen
Argyl.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 337 and 342.
 Interstate 78 in Pennsylvania between mile markers 63 and 76.
 Interstate 78 in New Jersey between mile markers 0 and 23.

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 northwestern
New Jersey...and southeastern Pennsylvania.

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

&&

LAT...LON 4075 7486 4071 7475 4003 7521 4053 7532
      4060 7552 4089 7526 4090 7523 4091 7524
      4093 7522 4094 7518 4095 7517 4095 7515
TIME...MOT...LOC 2108Z 197DEG 62KT 4088 7541 4056 7509 

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

JEO

012 
WWUS51 KPHI 302123
SVSPHI

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

NJC019-041-PAC017-077-091-095-101-302132-
/O.EXP.KPHI.SV.W.0305.000000T0000Z-201130T2130Z/
Hunterdon NJ-Warren NJ-Lehigh PA-Montgomery PA-Bucks PA-
Philadelphia PA-Northampton PA-
423 PM EST Mon Nov 30 2020

...THE SEVERE THUNDERSTORM WARNING FOR HUNTERDON...SOUTHWESTERN
WARREN...EAST CENTRAL LEHIGH...SOUTHEASTERN MONTGOMERY...CENTRAL
BUCKS...NORTHWESTERN PHILADELPHIA AND NORTHAMPTON COUNTIES WILL
EXPIRE AT 430 PM EST...
            
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 Tornado Watch remains in effect until 700 PM EST for northwestern
New Jersey...and southeastern Pennsylvania.

LAT...LON 4075 7486 4071 7475 4003 7521 4053 7532
      4060 7552 4089 7526 4090 7523 4091 7524
      4093 7522 4094 7518 4095 7517 4095 7515
TIME...MOT...LOC 2122Z 197DEG 62KT 4088 7541 4056 7509 

$$

JEO

The office that day

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

Issued	Product	Office	Counties	Lasted
Nov 30, 12:52 PM EST	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 5 more	92 min
Nov 30, 1:28 PM EST	Areal Flood Advisory	PHI	Hunterdon, Warren	2 hr
Nov 30, 2:01 PM EST	Coastal Flood Statement	PHI	Ocean	3 hr
Nov 30, 2:01 PM EST	Areal Flood Warning	PHI	Hunterdon, Mercer, Middlesex, Somerset	9 hr
Nov 30, 2:18 PM EST	Coastal Flood Advisory	PHI	Burlington, Camden, Gloucester	2 hr
Nov 30, 2:34 PM EST	Special Weather Statement	PHI	Morris, Sussex	56 min
Nov 30, 2:48 PM EST	Areal Flood Warning	PHI	Gloucester, Salem	8 hr
Nov 30, 3:01 PM EST	Severe Thunderstorm Warning	PHI	Gloucester, Salem	44 min
Nov 30, 3:26 PM EST	Areal Flood Warning	PHI	Hunterdon, Warren	4 hr
Nov 30, 3:37 PM EST	Special Marine Warning	PHI		38 min
Nov 30, 3:47 PM EST	Tornado Warning	PHI	Cumberland, Salem	28 min
Nov 30, 3:53 PM EST	Areal Flood Warning	PHI	Hunterdon, Morris, Somerset, Sussex, Warren	16 hr
Nov 30, 3:53 PM EST	Tornado Warning	PHI	Hunterdon	13 min
Nov 30, 3:58 PM EST	Small Craft Advisory	PHI		56 hr
Nov 30, 4:17 PM EST	Areal Flood Warning	PHI	Camden, Hunterdon, Mercer, Middlesex	10 hr
Nov 30, 4:49 PM EST	Severe Thunderstorm Warning	PHI	Camden, Cumberland, Gloucester, Salem	41 min
Nov 30, 5:05 PM EST	Special Marine Warning	PHI		40 min
Nov 30, 5:29 PM EST	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Somerset	46 min
Nov 30, 5:36 PM EST	River Flood Warning	PHI	Hunterdon, Somerset	7 hr
Nov 30, 12:15 PM EST	Areal Flood Advisory	PHI	Chester, Delaware	3 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, 2:41 PM EST	Severe Thunderstorm Warning	PHI	Chester, Delaware	49 min
Nov 30, 3:51 PM EST	River Flood Warning	PHI	Chester	14 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 New Jersey, 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.