Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 6, NWS Philadelphia/Mount Holly

February 7, 20206 counties in Pennsylvania; Hunterdon County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Feb 7, 2020, 9:43 AM EST for 6 counties in Pennsylvania; Hunterdon County, Warren County, New Jersey. It was in force for 62 min. 14 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: Feb 7, 2020, 9:43 AM EST (14:43 UTC)
Expired: Feb 7, 2020, 10:45 AM EST
In force: 62 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 70.0 mph

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

The radar

The Philadelphia radar (KDIX), 94 km from the middle of the area, began a volume at 14:45 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
Feb 7, 9:48 AM EST	TSTM WND DMG	3 Nne Upper Macungie Tw, PA	DOWNED TREE ON WIRES. TIME ESTIMATED FROM RADAR.
Feb 7, 9:50 AM EST	TSTM WND DMG	Pughtown, PA	SEVERAL REPORTS OF TREES AND POWER LINES DOWN NEAR PUGHTOWN, ROYERSFORD, PHOENIXVILLE, AND ST. PETERS. TIME ESTIMATED FROM RADAR.
Feb 7, 10:04 AM EST	TSTM WND DMG	2 Ssw Skippack, PA	SEVERAL REPORTS OF POWER LINES DOWN NEAR EVANSBURG STATE PARK. TIME ESTIMATED FROM RADAR.
Feb 7, 10:07 AM EST	TSTM WND DMG	2 Se Kulpsville, PA	SEVERAL LARGE TREES SNAPPED OR UPROOTED NEAR THE BORDER OF UPPER GWYNEDD AND TOWAMENCIN TWPS. MULTIPLE PROPERTIES DAMAGED DUE TO DOWNED TREES AND LIMBS. TIME ESTIMATED FROM RADAR.
Feb 7, 10:08 AM EST	TSTM WND DMG	Lansdale, PA	TREES AND POWER LINES DOWN IN LANSDALE. TIME ESTIMATED FROM RADAR.
Feb 7, 10:10 AM EST	TSTM WND DMG	Upper Gwynedd, PA	REPORTS OVER SOCIAL MEDIA WITH PHOTOS OF MULTIPLE TREES DOWN. TIME ESTIMATED FROM RADAR.
Feb 7, 10:12 AM EST	TSTM WND DMG	1 Ese Delps, PA	DOWNED TREE ON WIRES. TIME ESTIMATED FROM RADAR.
Feb 7, 10:18 AM EST	TSTM WND DMG	1 W Horsham Twp, PA	DOWNED TREE NEAR THE INTERSECTION OF CEDAR HILL ROAD AND STONGS LANE. TIME ESTIMATED FROM RADAR.
Feb 7, 10:26 AM EST	TSTM WND DMG	Buckingham Twp, PA	SEVERAL REPORTS OF POWER OUTAGES IN BUCKINGHAM, PINEVILLE, AND LAHASKA AREAS. TIME ESTIMATED FROM RADAR.
Feb 7, 10:32 AM EST	TSTM WND DMG	1 Nnw Tinicum Twp, PA	DOWNED TREES FROM STRONG WINDS. TIME ESTIMATED FROM RADAR.
Feb 7, 10:36 AM EST	TSTM WND DMG	1 S Sergeantsville, NJ	DOWNED TREES AND WIRES NEAR THE INTERSECTION OF SANDY RIDGE ROAD AND RITTENHOUSE ROAD. TIME ESTIMATED FROM RADAR.
Feb 7, 10:38 AM EST	TSTM WND DMG	1 Se Lambertville, NJ	DOWNED TREE AND WIRES NEAR LINCOLN AVENUE AND STUDDIFORD STREET. TIME ESTIMATED FROM RADAR.
Feb 7, 10:40 AM EST	TSTM WND GST 54	4 Se Sand Brook, NJ	TIME ESTIMATED FROM RADAR. SOME SMALL TREE LIMBS DOWN.
Feb 7, 10:44 AM EST	TSTM WND DMG	2 W Mcpherson, NJ	DOWNED TREE ON NJ-31 NORTHBOUND NORTH OF CR 623. TIME ESTIMATED FROM RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 2.7 hours before the alert went out and 197 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: 469 m above ground
0-6 km bulk shear: 105 kt
0-1 km storm-relative helicity: 650 m²/s²
0-3 km storm-relative helicity: 811 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

919 
WUUS51 KPHI 071443
SVRPHI
NJC019-041-PAC011-017-029-077-091-095-071545-
/O.NEW.KPHI.SV.W.0006.200207T1443Z-200207T1545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
943 AM EST Fri Feb 7 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...
  Lehigh County in eastern Pennsylvania...
  Montgomery County in southeastern Pennsylvania...
  Bucks County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...
  Northampton County in eastern Pennsylvania...

* Until 1045 AM EST.

* At 942 AM EST, severe thunderstorms were located along a line
  extending from near Bally to near Lionville-Marchwood, moving
  northeast at 45 mph.

  HAZARD...70 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Allentown, Easton, Bethlehem, Pottstown, Phoenixville, Lansdale,
  West Norriton, Forks, East Norriton, Emmaus, Northampton,
  Quakertown, Perkasie, Doylestown, Byram, Wilson, Downingtown,
  Souderton, Bedminster and Washington.

This includes the following highways...
 Interstate 78 in New Jersey between mile markers 0 and 17.
 Interstate 80 in New Jersey between mile markers 2 and 4.
 Interstate 78 in Pennsylvania between mile markers 41 and 76.
 Pennsylvania Turnpike between exits 312 and 320.
 Northeast Extension between exits A31 and A56.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.

&&

LAT...LON 4043 7475 4041 7481 4038 7481 4038 7486
      4035 7486 4034 7493 4033 7492 3999 7572
      4055 7583 4075 7574 4078 7565 4083 7538
      4086 7529 4090 7523 4093 7522 4097 7512
TIME...MOT...LOC 1442Z 233DEG 40KT 4046 7563 4002 7563 

HAIL...0.75IN
WIND...70MPH
 
$$

Staarmann

2 follow-up statements

160 
WWUS51 KPHI 071514
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1014 AM EST Fri Feb 7 2020

PAC011-029-077-071524-
/O.CAN.KPHI.SV.W.0006.000000T0000Z-200207T1545Z/
Berks PA-Lehigh PA-Chester PA-
1014 AM EST Fri Feb 7 2020

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN BERKS...LEHIGH AND
NORTHEASTERN CHESTER COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled, but gusty winds are 
still expected to persist behind the storms.

LAT...LON 4043 7475 4038 7487 4035 7486 4034 7494
      4015 7534 4045 7545 4054 7533 4058 7540
      4062 7538 4066 7542 4066 7548 4074 7553
      4074 7559 4078 7561 4086 7529 4090 7523
      4093 7522 4097 7512
TIME...MOT...LOC 1514Z 233DEG 40KT 4067 7527 4023 7527 

$$

NJC019-041-PAC017-091-095-071545-
/O.CON.KPHI.SV.W.0006.000000T0000Z-200207T1545Z/
Hunterdon NJ-Warren NJ-Montgomery PA-Bucks PA-Northampton PA-
1014 AM EST Fri Feb 7 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM EST
FOR HUNTERDON...SOUTHWESTERN WARREN...CENTRAL MONTGOMERY...BUCKS AND
NORTHAMPTON COUNTIES...

At 1014 AM EST, severe thunderstorms were located along a line
extending from Old Orchard to Lansdale, moving northeast at 45 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Easton, Bethlehem, Lansdale, Forks, East Norriton, Northampton,
Quakertown, Perkasie, Doylestown, Byram, Wilson, Souderton,
Bedminster, Washington, Hellertown, Nazareth, Bangor, Flemington,
Chalfont and Tinicum.

This includes the following highways...
 Interstate 78 in New Jersey between mile markers 0 and 17.
 Interstate 80 in New Jersey between mile markers 2 and 4.
 Interstate 78 in Pennsylvania between mile markers 65 and 76.
 Northeast Extension between exits A31 and A44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.

&&

LAT...LON 4043 7475 4038 7487 4035 7486 4034 7494
      4015 7534 4045 7545 4054 7533 4058 7540
      4062 7538 4066 7542 4066 7548 4074 7553
      4074 7559 4078 7561 4086 7529 4090 7523
      4093 7522 4097 7512
TIME...MOT...LOC 1514Z 233DEG 40KT 4067 7527 4023 7527 

HAIL...0.75IN
WIND...70MPH
 
$$

NC

838 
WWUS51 KPHI 071531
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1031 AM EST Fri Feb 7 2020

NJC041-PAC095-071540-
/O.CAN.KPHI.SV.W.0006.000000T0000Z-200207T1545Z/
Warren NJ-Northampton PA-
1031 AM EST Fri Feb 7 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN WARREN AND
NORTHAMPTON COUNTIES IS CANCELLED...

The storms which prompted the warning have weakened Therefore, the 
warning has been cancelled, but gusty winds will remain behind the 
line of storms.

LAT...LON 4043 7475 4042 7480 4038 7487 4035 7486
      4034 7494 4015 7534 4045 7545 4058 7527
      4061 7520 4059 7518 4063 7515 4073 7495
TIME...MOT...LOC 1530Z 233DEG 40KT 4077 7510 4033 7510 

$$

NJC019-PAC017-091-071545-
/O.CON.KPHI.SV.W.0006.000000T0000Z-200207T1545Z/
Hunterdon NJ-Montgomery PA-Bucks PA-
1031 AM EST Fri Feb 7 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM EST
FOR HUNTERDON...CENTRAL MONTGOMERY AND BUCKS COUNTIES...

At 1030 AM EST, severe thunderstorms were located along a line
extending from Roxburg to Doylestown, moving northeast at 45 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Lansdale, East Norriton, Quakertown, Perkasie, Doylestown, Byram,
Souderton, Bedminster, Flemington, Chalfont, Tinicum, High Bridge,
Hatfield, Clinton, New Hope, Dublin, Glen Gardner, Ferndale, Hampton
and Frenchtown.

This includes the following highways...
 Interstate 78 in New Jersey between mile markers 7 and 17.
 Northeast Extension between exits A31 and A44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.

&&

LAT...LON 4043 7475 4042 7480 4038 7487 4035 7486
      4034 7494 4015 7534 4045 7545 4058 7527
      4061 7520 4059 7518 4063 7515 4073 7495
TIME...MOT...LOC 1530Z 233DEG 40KT 4077 7510 4033 7510 

HAIL...0.75IN
WIND...70MPH
 
$$

NC

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 7, 4:00 AM EST	Winter Weather Advisory	PHI	Carbon, Monroe	14 hr
Feb 7, 8:03 AM EST	Coastal Flood Advisory	PHI	Bucks, Delaware, Philadelphia	11 hr
Feb 7, 8:52 AM EST	Severe Thunderstorm Warning	PHI	Berks, Chester, Delaware, Montgomery	53 min
Feb 7, 9:36 AM EST	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	39 min
Feb 7, 9:39 AM EST	Tornado Warning	PHI	Chester, Delaware	36 min
Feb 7, 10:14 AM EST	Severe Thunderstorm Warning	PHI	Bucks, Montgomery, Philadelphia	61 min
Feb 6, 8:13 PM EST	Storm Warning	PHI		21 hr
Feb 6, 8:24 PM EST	High Wind Warning	PHI	Atlantic, Burlington, Cape May, Cumberland, Monmouth, Ocean	21 hr
Feb 7, 8:18 AM EST	Coastal Flood Statement	PHI	Ocean	11 hr
Feb 7, 10:10 AM EST	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more	65 min
Feb 7, 10:43 AM EST	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Morris, Somerset, Sussex, Warren	47 min
Feb 7, 11:01 AM EST	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth, Ocean	44 min
Feb 7, 3:27 PM EST	Gale Warning	PHI		9 hr
Feb 7, 6:53 PM EST	Low Water Advisory	PHI		9 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.