Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 157, NWS Philadelphia/Mount Holly

July 22, 20205 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 22, 2020, 4:25 PM EDT for 5 counties in Pennsylvania. It was in force for 50 min. 10 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: Jul 22, 2020, 4:25 PM EDT (20:25 UTC)
Expired: Jul 22, 2020, 5:15 PM EDT
In force: 50 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 126 km from the middle of the area, began a volume at 20:28 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
Jul 22, 4:30 PM EDT	TSTM WND DMG	2 Nw Richmond Twp, PA	DOWNED TREE ON MOSELEM SPRINGS RD. TIME ESTIMATED FROM RADAR.
Jul 22, 4:32 PM EDT	TSTM WND DMG	Mohnton, PA	DOWNED WIRES ON WYOMISSING AVENUE IN MOHNTON. TIME ESTIMATED FROM RADAR.
Jul 22, 4:33 PM EDT	TSTM WND DMG	2 Ne Mount Penn, PA	DOWNED TREE IN WIRES ON HOLLYWOOD DR. TIME ESTIMATED FROM RADAR.
Jul 22, 4:34 PM EDT	TSTM WND DMG	2 Se Mohnton, PA	DOWNED WIRES ON LEDGE ROCK ROAD EAST OF MOHNTON. TIME ESTIMATED FROM RADAR.
Jul 22, 4:51 PM EDT	TSTM WND DMG	1 E Earl Twp, PA	DOWNED TREES AND WIRES NEAR WEST PHILADELPHIA AVENUE IN EARL TWP. TIME ESTIMATED FROM RADAR.
Jul 22, 4:51 PM EDT	TSTM WND DMG	2 Se Union Twp, PA	TREE DOWN ON SHED ROAD IN UNION TWP. TIME ESTIMATED FROM RADAR.
Jul 22, 4:53 PM EDT	TSTM WND DMG	1 Wnw Washington Twp, PA	TREE DOWN ON WIRES WITH TRANSFORMER BLOWN ON ANTHONYS MILL RD. TIME ESTIMATED FROM RADAR.
Jul 22, 5:01 PM EDT	TSTM WND DMG	3 N Warwick Twp, PA	DOWNED WIRES NEAR HOPEWELL ROAD NEAR THE BERKS/CHESTER COUNTY BORDER. TIME ESTIMATED FROM RADAR.
Jul 22, 5:22 PM EDT	TSTM WND DMG	1 Ese Trappe, PA	TREE AND/OR WIRES DOWN ON COLLEGE AVE AT 3RD AVE. TIME ESTIMATED FROM RADAR.
Jul 22, 5:25 PM EDT	TSTM WND DMG	2 Nnw West Rockhill Twp, PA	DOWNED TREES AND WIRES NEAR SCHUKRAFT ROAD IN WEST ROCKHILL 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.

Issued	Product	Office	Lasted
Jul 22, 2:57 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.4 hours before the alert went out and 206 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: 248 J/kg
Mixed-layer CIN: -214 J/kg
Mixed-layer LCL: 1163 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 20 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

868 
WUUS51 KPHI 222025
SVRPHI
PAC011-017-029-077-091-222115-
/O.NEW.KPHI.SV.W.0157.200722T2025Z-200722T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
425 PM EDT Wed Jul 22 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southeastern Berks County in eastern Pennsylvania...
  South central Lehigh County in eastern Pennsylvania...
  Northwestern Montgomery County in southeastern Pennsylvania...
  West central Bucks County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...

* Until 515 PM EDT.

* At 424 PM EDT, a severe thunderstorm was located over Wyomissing,
  or near Reading, moving east at 40 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Reading, Pottstown, Phoenixville, Wyomissing, Quakertown,
  Birdsboro, Collegeville, Royersford, Fleetwood, Sinking Spring,
  Laureldale, Trappe, East Greenville, Wernersville, Leesport,
  Schwenksville, Shoemakersville, Elverson, Bally and Bechtelsville.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 303.
 Northeast Extension between mile markers 34 and 46.
 Interstate 176 in Pennsylvania between mile markers 1 and 11.

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 this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

&&

LAT...LON 4052 7604 4046 7527 4011 7549 4014 7588
      4029 7611
TIME...MOT...LOC 2024Z 279DEG 35KT 4031 7598 

HAIL...0.88IN
WIND...60MPH
 
$$

CMS

2 follow-up statements

048 
WWUS51 KPHI 222038
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
438 PM EDT Wed Jul 22 2020

PAC011-017-029-077-091-222115-
/O.CON.KPHI.SV.W.0157.000000T0000Z-200722T2115Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-Chester PA-
438 PM EDT Wed Jul 22 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR SOUTHEASTERN BERKS...SOUTH CENTRAL LEHIGH...NORTHWESTERN
MONTGOMERY...WEST CENTRAL BUCKS AND NORTHEASTERN CHESTER COUNTIES...

At 438 PM EDT, a severe thunderstorm was located near Birdsboro, or
near Reading, moving east at 40 mph.

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

SOURCE...Law enforcement. Several reports of tree damage have been 
         received near and east of Reading.

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

Locations impacted include...
Reading, Pottstown, Phoenixville, Wyomissing, Quakertown, Birdsboro,
Collegeville, Royersford, Fleetwood, Sinking Spring, Laureldale,
Trappe, East Greenville, Wernersville, Leesport, Schwenksville,
Elverson, Bally, Bechtelsville and Green Lane.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 303.
 Northeast Extension between mile markers 34 and 46.
 Interstate 176 in Pennsylvania between mile markers 1 and 11.

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 this storm. 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 4050 7594 4046 7527 4011 7549 4014 7588
      4029 7611
TIME...MOT...LOC 2038Z 269DEG 35KT 4030 7585 

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

CMS

446 
WWUS51 KPHI 222102
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
502 PM EDT Wed Jul 22 2020

PAC011-017-029-077-091-222115-
/O.CON.KPHI.SV.W.0157.000000T0000Z-200722T2115Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-Chester PA-
502 PM EDT Wed Jul 22 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR SOUTHEASTERN BERKS...SOUTH CENTRAL LEHIGH...NORTHWESTERN
MONTGOMERY...WEST CENTRAL BUCKS AND NORTHEASTERN CHESTER COUNTIES...

At 501 PM EDT, a severe thunderstorm was located over Pottstown, or
16 miles east of Reading, moving east at 40 mph.

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

SOURCE...Law enforcement. Numerous reports of wind damage have been 
         received in Berks County, especially east of Reading.

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

Locations impacted include...
Reading, Pottstown, Phoenixville, Quakertown, Birdsboro,
Collegeville, Royersford, Fleetwood, Trappe, East Greenville,
Schwenksville, Elverson, Bally, Bechtelsville, Green Lane, Lyons, New
Morgan, Pughtown, Spring Mount and Geryville.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 303.
 Northeast Extension between mile markers 34 and 46.
 Interstate 176 in Pennsylvania between mile markers 1 and 11.

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 this storm. 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 4046 7527 4011 7549 4014 7588 4023 7601
      4049 7582
TIME...MOT...LOC 2101Z 269DEG 35KT 4028 7562 

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

CMS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 8:45 PM EDT	Special Weather Statement	PHI	Berks	30 min
Jul 21, 9:20 PM EDT	Special Weather Statement	PHI	Montgomery	25 min
Jul 22, 1:36 PM EDT	Special Weather Statement	PHI	Carbon	24 min
Jul 22, 1:58 PM EDT	Special Weather Statement	PHI	Monroe	32 min
Jul 22, 2:10 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	50 min
Jul 22, 3:29 PM EDT	Special Weather Statement	PHI	Lebanon	46 min
Jul 22, 3:39 PM EDT	Severe Thunderstorm Warning	PHI	Berks	51 min
Jul 22, 4:01 PM EDT	Severe Thunderstorm Warning	PHI	Chester	22 min
Jul 22, 4:10 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Northampton	65 min
Jul 22, 4:38 PM EDT	Severe Thunderstorm Warning	PHI	Chester	52 min
Jul 22, 4:49 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Carbon, Lehigh, Monroe, Northampton	56 min
Jul 22, 5:09 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Delaware, Lehigh, Montgomery and 1 more	66 min
Jul 22, 5:16 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Monroe, Northampton	59 min
Jul 22, 5:23 PM EDT	Areal Flood Advisory	PHI	Northampton	3 hr
Jul 22, 5:33 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	57 min
Jul 22, 5:40 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery, Philadelphia	65 min

Nearby

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.