Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 138, NWS Philadelphia/Mount Holly

June 20, 20194 states

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 20, 2019, 2:33 PM EDT for 4 states. It was in force for 57 min. 2 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: Jun 20, 2019, 2:33 PM EDT (18:33 UTC)
Expired: Jun 20, 2019, 3:30 PM EDT
In force: 57 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

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

The radar

The Philadelphia radar (KDIX), 93 km from the middle of the area, began a volume at 18:37 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
Jun 20, 2:45 PM EDT	TSTM WND DMG	1 Wnw Pennsbury Twp, PA	DOWNED TREE INTO WIRES ON PARKERSVILLE ROAD. TIME ESTIMATED FROM RADAR.
Jun 20, 3:03 PM EDT	TSTM WND DMG	West Conshohocken, PA	MATSONFORD ROAD BLOCKED IN BOTH DIRECTIONS BETWEEN I-76 AND I-476 DUE TO A FALLEN TREE.

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 6.6 hours before the alert went out and 192 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: 213 J/kg
Mixed-layer CIN: -80 J/kg
Mixed-layer LCL: 1000 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 56 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

676 
WUUS51 KPHI 201833
SVRPHI
DEC003-MDC015-NJC015-033-PAC029-045-091-101-201930-
/O.NEW.KPHI.SV.W.0138.190620T1833Z-190620T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
233 PM EDT Thu Jun 20 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern New Castle County in northern Delaware...
  Northeastern Cecil County in northeastern Maryland...
  Northwestern Salem County in southern New Jersey...
  Northwestern Gloucester County in southern New Jersey...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Central Chester County in southeastern Pennsylvania...
  Western Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 330 PM EDT.

* At 232 PM EDT, severe thunderstorms were located along a line
  extending from Lionville to Kemblesville, moving east at 30 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Wilmington, Newark, West Chester, Norristown,
  Chester, Phoenixville, West Norriton, East Norriton, Pennsville,
  Coatesville, Yeadon, Westtown, Carneys Point, Downingtown,
  Conshohocken, Hatboro, Folcroft, Ambler and Swarthmore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to damaging winds, frequent cloud to ground lightning is 
occurring with these storms. Move indoors immediately. Remember, if 
you can hear thunder, you are close enough to be struck by lightning.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4012 7574 4019 7510 4014 7503 3965 7533
      3966 7552 3971 7549 3972 7551 3966 7556
      3967 7597
TIME...MOT...LOC 1832Z 265DEG 25KT 4005 7566 3976 7584 

HAIL...0.75IN
WIND...60MPH
 
$$

Meola/Gorse

3 follow-up statements

388 
WWUS51 KPHI 201859
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
259 PM EDT Thu Jun 20 2019

MDC015-201908-
/O.CAN.KPHI.SV.W.0138.000000T0000Z-190620T1930Z/
Cecil MD-
259 PM EDT Thu Jun 20 2019

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CECIL COUNTY IS
CANCELLED...

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

LAT...LON 3978 7564 3994 7564 4015 7548 4019 7510
      4014 7503 3965 7533 3966 7552 3971 7549
      3972 7551 3966 7556 3967 7579 3969 7579
TIME...MOT...LOC 1858Z 269DEG 28KT 4005 7532 3979 7555 

$$

DEC003-NJC015-033-PAC029-045-091-101-201930-
/O.CON.KPHI.SV.W.0138.000000T0000Z-190620T1930Z/
New Castle DE-Salem NJ-Gloucester NJ-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
259 PM EDT Thu Jun 20 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR NORTHERN NEW CASTLE...NORTHWESTERN SALEM...NORTHWESTERN
GLOUCESTER...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN CHESTER...WESTERN
PHILADELPHIA AND DELAWARE COUNTIES...

At 258 PM EDT, severe thunderstorms were located along a line
extending from Bryn Mawr to Talleyville, moving east at 30 mph.

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

SOURCE...Radar indicated.

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

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3978 7564 3994 7564 4015 7548 4019 7510
      4014 7503 3965 7533 3966 7552 3971 7549
      3972 7551 3966 7556 3967 7579 3969 7579
TIME...MOT...LOC 1858Z 269DEG 28KT 4005 7532 3979 7555 

HAIL...0.75IN
WIND...60MPH
 
$$

Staarmann

101 
WWUS51 KPHI 201916
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
316 PM EDT Thu Jun 20 2019

PAC029-201924-
/O.CAN.KPHI.SV.W.0138.000000T0000Z-190620T1930Z/
Chester PA-
316 PM EDT Thu Jun 20 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHESTER COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled. A Flash Flood 
Warning remains in effect for portions of eastern Chester County 
until 645 PM.

LAT...LON 3981 7553 3983 7547 4006 7539 4008 7533
      4017 7533 4019 7510 4014 7503 3965 7533
      3966 7552 3971 7549 3972 7551 3966 7556
      3966 7562
TIME...MOT...LOC 1914Z 267DEG 25KT 4006 7517 3975 7538 

$$

DEC003-NJC015-033-PAC045-091-101-201930-
/O.CON.KPHI.SV.W.0138.000000T0000Z-190620T1930Z/
New Castle DE-Salem NJ-Gloucester NJ-Montgomery PA-Philadelphia PA-
Delaware PA-
316 PM EDT Thu Jun 20 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR NORTHEASTERN NEW CASTLE...NORTHWESTERN SALEM...NORTHWESTERN
GLOUCESTER...SOUTHEASTERN MONTGOMERY...WESTERN PHILADELPHIA AND
DELAWARE COUNTIES...

At 314 PM EDT, severe thunderstorms were located along a line
extending from Germantown to Beckett, moving east at 30 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Philadelphia, Wilmington, Norristown, Chester, East Norriton,
Pennsville, Yeadon, Carneys Point, Conshohocken, Hatboro, Folcroft,
Ambler, Swarthmore, Paulsboro, New Castle, Penns Grove, Jenkintown,
Narberth, Woodstown and National Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3981 7553 3983 7547 4006 7539 4008 7533
      4017 7533 4019 7510 4014 7503 3965 7533
      3966 7552 3971 7549 3972 7551 3966 7556
      3966 7562
TIME...MOT...LOC 1914Z 267DEG 25KT 4006 7517 3975 7538 

HAIL...0.75IN
WIND...60MPH
 
$$

Staarmann

456 
WWUS51 KPHI 201929
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
329 PM EDT Thu Jun 20 2019

DEC003-NJC015-033-PAC045-091-101-201938-
/O.EXP.KPHI.SV.W.0138.000000T0000Z-190620T1930Z/
New Castle DE-Salem NJ-Gloucester NJ-Montgomery PA-Philadelphia PA-
Delaware PA-
329 PM EDT Thu Jun 20 2019

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN NEW CASTLE...
NORTHWESTERN SALEM...NORTHWESTERN GLOUCESTER...SOUTHEASTERN
MONTGOMERY...WESTERN PHILADELPHIA AND DELAWARE COUNTIES WILL EXPIRE
AT 330 PM EDT...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore, the warning will
be allowed to expire.

LAT...LON 3981 7553 3983 7547 4006 7539 4008 7533
      4017 7533 4019 7510 4014 7503 3965 7533
      3966 7552 3971 7549 3972 7551 3966 7556
      3966 7562
TIME...MOT...LOC 1928Z 265DEG 25KT 4007 7505 3976 7526 

$$

Gorse

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 19, 9:09 PM EDT	Areal Flood Warning	PHI	Philadelphia	3 hr
Jun 19, 9:50 PM EDT	Special Weather Statement	PHI	Lebanon	55 min
Jun 19, 10:47 PM EDT	Areal Flood Advisory	PHI	Berks	50 min
Jun 19, 11:11 PM EDT	Flash Flood Warning	PHI	Chester, Delaware	6 hr
Jun 19, 11:34 PM EDT	Flash Flood Warning	PHI	Berks	6 hr
Jun 20, 12:39 AM EDT	Areal Flood Advisory	PHI	Montgomery	7 min
Jun 20, 12:45 AM EDT	Flash Flood Warning	PHI	Montgomery, Philadelphia	6 hr
Jun 20, 3:40 AM EDT	River Flood Warning	PHI	Delaware	111 min
Jun 20, 3:59 AM EDT	River Flood Warning	PHI	Chester	7 hr
Jun 20, 5:10 AM EDT	Areal Flood Warning	PHI	Chester, Delaware	12 hr
Jun 20, 5:19 AM EDT	River Flood Warning	PHI	Chester, Delaware	13 hr
Jun 20, 5:24 AM EDT	Areal Flood Warning	PHI	Berks	6 hr
Jun 20, 6:14 AM EDT	Areal Flood Warning	PHI	Montgomery, Philadelphia	10 hr
Jun 20, 6:31 AM EDT	River Flood Warning	PHI	Delaware	3 hr
Jun 20, 1:24 PM EDT	Special Weather Statement	PHI	Berks, Chester, Montgomery	51 min
Jun 20, 1:28 PM EDT	Areal Flood Advisory	PHI	Berks	4 hr
Jun 20, 2:13 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Chester, Delaware, Lehigh, Montgomery	4 hr
Jun 20, 2:26 PM EDT	Special Weather Statement	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	94 min
Jun 20, 2:48 PM EDT	Flash Flood Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	4 hr
Jun 20, 3:20 PM EDT	Flash Flood Warning	PHI	Bucks	4 hr
Jun 20, 4:58 PM EDT	River Flood Warning	PHI	Chester	4 hr
Jun 20, 6:33 PM EDT	Areal Flood Warning	PHI	Montgomery	3 hr
Jun 19, 8:36 PM EDT	Areal Flood Advisory	PHI	Ocean	2 hr
Jun 19, 8:39 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Ocean	2 hr
Jun 19, 11:19 PM EDT	Flash Flood Warning	PHI	Camden, Gloucester, Salem	5 hr
Jun 19, 11:25 PM EDT	Areal Flood Warning	PHI	Burlington	5 hr
Jun 20, 1:49 AM EDT	Flash Flood Warning	PHI	Burlington	3 hr
Jun 20, 4:32 AM EDT	Marine Dense Fog Advisory	PHI		5 hr
Jun 20, 4:38 AM EDT	Areal Flood Warning	PHI	Burlington, Camden, Gloucester	14 hr
Jun 20, 3:21 PM EDT	Special Weather Statement	PHI	Atlantic	24 min
Jun 20, 3:36 PM EDT	Special Weather Statement	PHI	Burlington, Mercer, Middlesex, Ocean	54 min
Jun 20, 4:05 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Middlesex, Monmouth, Ocean	4 hr
Jun 20, 4:06 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	54 min
Jun 20, 4:23 PM EDT	Special Weather Statement	PHI	Cumberland	37 min
Jun 20, 4:24 PM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Monmouth, Morris, Somerset	3 hr
Jun 20, 4:26 PM EDT	Special Marine Warning	PHI		64 min
Jun 20, 4:40 PM EDT	Special Weather Statement	PHI	Ocean	35 min
Jun 20, 4:44 PM EDT	Severe Thunderstorm Warning	PHI	Monmouth, Ocean	31 min
Jun 20, 5:10 PM EDT	Special Weather Statement	PHI	Atlantic	35 min
Jun 20, 5:15 PM EDT	Special Marine Warning	PHI		90 min
Jun 20, 6:50 PM EDT	Areal Flood Warning	PHI	Burlington	10 hr
Jun 19, 11:46 PM EDT	River Flood Warning	PHI	New Castle	104 min
Jun 20, 7:55 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	4 hr
Jun 20, 3:48 PM EDT	Special Weather Statement	PHI	Cecil	27 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019 Severe Thunderstorm Warnings in New Jersey, 2019 Severe Thunderstorm Warnings in Delaware, 2019 Every severe thunderstorm warning in 2019

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.