Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 76, NWS Philadelphia/Mount Holly

July 1, 20175 counties in Pennsylvania; Camden County, Gloucester County, Salem County, New Jersey; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 1, 2017, 5:01 PM EDT for 5 counties in Pennsylvania; Camden County, Gloucester County, Salem County, New Jersey; New Castle County, Delaware. It was in force for 44 min. 1 report 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 1, 2017, 5:01 PM EDT (21:01 UTC)
Expired: Jul 1, 2017, 5:45 PM EDT
In force: 44 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 0.88 in
Wind: 60.0 mph

Counties New Castle County, DE, Camden County, NJ, Gloucester County, NJ, Salem County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 69 km from the middle of the area, began a volume at 21:01 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 1, 5:39 PM EDT	TSTM WND DMG	Abington, PA	SEVERAL TREES AND POWER LINES DOWN IN ABINGTON. 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 1, 1:34 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.0 hours before the alert went out and 217 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: 160 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 564 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 95 m²/s²
0-3 km storm-relative helicity: 105 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

928 
WUUS51 KPHI 012101
SVRPHI
DEC003-NJC007-015-033-PAC017-029-045-091-101-012145-
/O.NEW.KPHI.SV.W.0076.170701T2101Z-170701T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
501 PM EDT SAT JUL 1 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern New Castle County in northern Delaware...
  Salem County in southern New Jersey...
  Northwestern Camden County in southern New Jersey...
  Gloucester County in southern New Jersey...
  Montgomery County in southeastern Pennsylvania...
  Southern Bucks County in southeastern Pennsylvania...
  Eastern Chester County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 545 PM EDT

* At 500 PM EDT, severe thunderstorms were located along a line
  extending from Spring Mount to Glen Westover, moving east at 40
  mph.

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

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Philadelphia, Trenton, Camden, Wilmington, Newark, West Chester,
  Gloucester City, Cherry Hill, Bensalem, Ewing, Norristown, Chester,
  Deptford, West Deptford, Glassboro, Lindenwold, Phoenixville,
  Lansdale, West Norriton and East Norriton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 4037 7552 4027 7485 4022 7477 4010 7484
      4005 7497 3999 7506 3999 7503 3998 7501
      3995 7502 3989 7494 3950 7515 3956 7524
      3948 7535 3965 7579 3972 7579 3973 7586
TIME...MOT...LOC 2100Z 289DEG 34KT 4027 7548 3971 7579 

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

SFJ

1 follow-up statement

972 
WWUS51 KPHI 012124
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
524 PM EDT SAT JUL 1 2017

DEC003-NJC007-015-033-PAC017-029-045-091-101-012145-
/O.CON.KPHI.SV.W.0076.000000T0000Z-170701T2145Z/
New Castle DE-Salem NJ-Camden NJ-Gloucester NJ-Montgomery PA-
Bucks PA-Chester PA-Philadelphia PA-Delaware PA-
524 PM EDT SAT JUL 1 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM EDT
FOR NORTHERN NEW CASTLE...SALEM...NORTHWESTERN CAMDEN...GLOUCESTER...
MONTGOMERY...SOUTHERN BUCKS...EASTERN CHESTER...PHILADELPHIA AND
DELAWARE COUNTIES...

At 524 PM EDT, severe thunderstorms were located along a line
extending from near Lansdale to Delaware Memorial Bridge, moving east
at 35 mph.

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

SOURCE...Trained weather spotters. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Philadelphia, Trenton, Camden, Wilmington, Newark, West Chester,
Gloucester City, Cherry Hill, Bensalem, Ewing, Norristown, Chester,
Deptford, West Deptford, Glassboro, Lindenwold, Phoenixville,
Lansdale, West Norriton and East Norriton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 4035 7543 4027 7485 4024 7483 4022 7477
      4010 7484 4007 7494 3999 7506 3998 7501
      3995 7502 3989 7494 3950 7515 3956 7524
      3948 7535 3965 7579 3972 7579
TIME...MOT...LOC 2124Z 278DEG 29KT 4025 7523 3969 7554 

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

SFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 8:09 PM EDT	Special Weather Statement	PHI	Montgomery	51 min
Jun 30, 8:32 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Lehigh, Montgomery	118 min
Jun 30, 9:17 PM EDT	Special Weather Statement	PHI	Bucks	43 min
Jul 1, 2:38 PM EDT	Special Weather Statement	PHI	Berks	52 min
Jul 1, 3:22 PM EDT	Special Weather Statement	PHI	Berks, Carbon	23 min
Jul 1, 3:24 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh	3 hr
Jul 1, 3:41 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh, Northampton	49 min
Jul 1, 4:05 PM EDT	Special Weather Statement	PHI	Chester	40 min
Jul 1, 4:20 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh	4 hr
Jul 1, 4:24 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Lehigh, Montgomery, Northampton	51 min
Jul 1, 5:00 PM EDT	Areal Flood Advisory	PHI	Bucks, Lehigh, Northampton	4 hr
Jul 1, 5:08 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh, Montgomery, Northampton	52 min
Jul 1, 5:30 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	4 hr
Jul 1, 5:35 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	40 min
Jul 1, 5:50 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	40 min
Jul 1, 6:17 PM EDT	Areal Flood Advisory	PHI	Monroe, Northampton	4 hr
Jun 30, 9:48 PM EDT	Special Weather Statement	PHI	Middlesex	42 min
Jun 30, 9:55 PM EDT	Special Weather Statement	PHI	Middlesex	20 min
Jun 30, 10:32 PM EDT	Special Weather Statement	PHI	Middlesex	28 min
Jul 1, 9:48 AM EDT	Marine Dense Fog Advisory	PHI		5 hr
Jul 1, 5:10 PM EDT	Special Marine Warning	PHI		95 min
Jul 1, 5:29 PM EDT	Special Weather Statement	PHI	Sussex	31 min
Jul 1, 5:41 PM EDT	Special Weather Statement	PHI	Atlantic, Cape May, Cumberland, Salem	34 min
Jul 1, 6:07 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Gloucester, Mercer	23 min
Jul 1, 6:22 PM EDT	Special Weather Statement	PHI	Middlesex, Monmouth, Morris	23 min
Jul 1, 6:33 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Cumberland, Gloucester	27 min
Jul 1, 6:59 PM EDT	Special Marine Warning	PHI		61 min
Jul 1, 7:01 PM EDT	Special Weather Statement	PHI	Atlantic, Burlington, Ocean	29 min
Jul 1, 5:39 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	51 min
Jul 1, 6:27 PM EDT	Special Weather Statement	PHI	Kent	33 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2017 Severe Thunderstorm Warnings in New Jersey, 2017 Severe Thunderstorm Warnings in Delaware, 2017 Every severe thunderstorm warning in 2017

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.