Alert archive / New Jersey / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 127, NWS Philadelphia/Mount Holly

July 24, 20175 counties in New Jersey; Kent County, New Castle County, Delaware; Delaware County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 24, 2017, 2:34 AM EDT for 5 counties in New Jersey; Kent County, New Castle County, Delaware; Delaware County, Philadelphia County, Pennsylvania. It was in force for 41 min. 5 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 24, 2017, 2:34 AM EDT (06:34 UTC)
Expired: Jul 24, 2017, 3:15 AM EDT
In force: 41 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Kent County, DE, New Castle County, DE, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Delaware County, PA, Philadelphia County, PA

The radar

The Dover AFB radar (KDOX), 75 km from the middle of the area, began a volume at 06:38 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 24, 2:55 AM EDT	TSTM WND DMG	2 E Swedesboro, NJ	TWO LARGE TREES DOWN ON BACK CREEK RD.
Jul 24, 3:00 AM EDT	TSTM WND DMG	Upper Deerfield Twp, NJ	TREE DOWN.
Jul 24, 3:09 AM EDT	TSTM WND DMG	Mantua, NJ	LARGE TREE DOWN ON JACKSON RD.
Jul 24, 3:12 AM EDT	TSTM WND DMG	Centerton, NJ	TREE DOWN ON A CAR. TIME ESTIMATED FROM RADAR.
Jul 24, 3:15 AM EDT	TSTM WND DMG	Vineland, NJ	TREE DOWN.

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

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 6.6 hours before the alert went out and 174 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: 771 J/kg
Mixed-layer CIN: -78 J/kg
Mixed-layer LCL: 995 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 160 m²/s²
0-3 km storm-relative helicity: 136 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 6.7

Open this sounding in Storm Lab

The text

As transmitted.

245 
WUUS51 KPHI 240634
SVRPHI
DEC001-003-NJC005-007-011-015-033-PAC045-101-240715-
/O.NEW.KPHI.SV.W.0127.170724T0634Z-170724T0715Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
234 AM EDT MON JUL 24 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  New Castle County in northern Delaware...
  Northern Kent County in central Delaware...
  Cumberland County in southern New Jersey...
  Salem County in southern New Jersey...
  Camden County in southern New Jersey...
  Gloucester County in southern New Jersey...
  Northwestern Burlington County in southern New Jersey...
  Southwestern Philadelphia County in southeastern Pennsylvania...
  Southeastern Delaware County in southeastern Pennsylvania...

* Until 315 AM EDT

* At 233 AM EDT, severe thunderstorms were located along a line
  extending from Arden to Green Spring, moving east at 35 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Philadelphia, Camden, Wilmington, Vineland, Millville, Bridgeton,
  Middletown, Gloucester City, Cherry Hill, Evesham, Mount Laurel,
  Chester, Willingboro, Deptford, Voorhees, Medford, West Deptford,
  Glassboro, Lindenwold and Pennsville.

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 this storm. 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 3979 7565 4008 7485 3987 7476 3960 7492
      3952 7499 3950 7496 3924 7505 3924 7528
      3939 7548 3939 7549 3927 7537 3923 7538
      3923 7568 3925 7576
TIME...MOT...LOC 0633Z 248DEG 30KT 3979 7551 3932 7566 

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

JRK

2 follow-up statements

132 
WWUS51 KPHI 240655
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
255 AM EDT MON JUL 24 2017

DEC001-003-240704-
/O.CAN.KPHI.SV.W.0127.000000T0000Z-170724T0715Z/
New Castle DE-Kent DE-
255 AM EDT MON JUL 24 2017

...THE SEVERE THUNDERSTORM WARNING FOR NEW CASTLE AND NORTHERN KENT
COUNTIES IS CANCELLED...

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

LAT...LON 3961 7491 3953 7499 3949 7496 3924 7505
      3924 7527 3940 7550 3948 7556 3973 7546
      3979 7541 3990 7537 4008 7485 3987 7476
TIME...MOT...LOC 0654Z 244DEG 28KT 3988 7534 3942 7543 3928 7530 

$$

NJC005-007-011-015-033-PAC045-101-240715-
/O.CON.KPHI.SV.W.0127.000000T0000Z-170724T0715Z/
Cumberland NJ-Salem NJ-Camden NJ-Gloucester NJ-Burlington NJ-
Philadelphia PA-Delaware PA-
255 AM EDT MON JUL 24 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 AM EDT
FOR CUMBERLAND...SALEM...CAMDEN...GLOUCESTER...NORTHWESTERN
BURLINGTON...SOUTHWESTERN PHILADELPHIA AND SOUTHEASTERN DELAWARE
COUNTIES...

At 254 AM EDT, severe thunderstorms were located along a line
extending from Swarthmore to Newport Meadows to 6 miles southwest of
Cedarville, moving northeast at 30 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

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

Locations impacted include...
Philadelphia, Camden, Vineland, Millville, Bridgeton, Gloucester
City, Cherry Hill, Evesham, Mount Laurel, Chester, Willingboro,
Deptford, Voorhees, Medford, West Deptford, Glassboro, Lindenwold,
Pennsville, Lumberton and Bellmawr.

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 this storm. 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 3961 7491 3953 7499 3949 7496 3924 7505
      3924 7527 3940 7550 3948 7556 3973 7546
      3979 7541 3990 7537 4008 7485 3987 7476
TIME...MOT...LOC 0654Z 244DEG 28KT 3988 7534 3942 7543 3928 7530 

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

JRK

270 
WWUS51 KPHI 240716
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
316 AM EDT MON JUL 24 2017

NJC005-007-011-015-033-PAC045-101-240722-
/O.EXP.KPHI.SV.W.0127.000000T0000Z-170724T0715Z/
Cumberland NJ-Salem NJ-Camden NJ-Gloucester NJ-Burlington NJ-
Philadelphia PA-Delaware PA-
316 AM EDT MON JUL 24 2017

...THE SEVERE THUNDERSTORM WARNING FOR CUMBERLAND...SALEM...CAMDEN...
GLOUCESTER...NORTHWESTERN BURLINGTON...CENTRAL PHILADELPHIA AND
SOUTHEASTERN DELAWARE COUNTIES WILL EXPIRE AT 315 AM EDT...
            
The storms which prompted the warning have weakened below severe 
limits, and no longer pose an immediate threat to life or property 
to the Philadelphia metropolitan area. Therefore the warning will be 
allowed to expire.  However gusty winds and heavy rain are still 
possible with these thunderstorms.

Farther south into Salem, southern Gloucester, southern Camden and 
Cumberland Counties, a Severe Thunderstorm Warning still remains in 
effect until 4 AM.

LAT...LON 3961 7491 3953 7499 3949 7496 3924 7505
      3924 7527 3940 7550 3948 7556 3973 7546
      3979 7541 3990 7537 4008 7485 3987 7476
TIME...MOT...LOC 0712Z 248DEG 30KT 3993 7517 3947 7526 3933 7513 

$$

JRK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 9:39 PM EDT	Areal Flood Advisory	PHI	Gloucester, Salem	4 hr
Jul 23, 10:18 PM EDT	Flash Flood Warning	PHI	Atlantic, Camden, Cumberland, Gloucester, Salem	8 hr
Jul 23, 10:23 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	52 min
Jul 23, 10:54 PM EDT	Special Weather Statement	PHI	Gloucester	51 min
Jul 23, 11:38 PM EDT	Tornado Warning	PHI	Atlantic, Cape May	37 min
Jul 23, 11:41 PM EDT	Special Marine Warning	PHI		64 min
Jul 23, 11:43 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Cumberland, Ocean, Salem	6 hr
Jul 23, 11:50 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Monmouth, Ocean	6 hr
Jul 24, 12:04 AM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Cumberland, Gloucester, Salem	41 min
Jul 24, 12:35 AM EDT	Special Marine Warning	PHI		55 min
Jul 24, 12:56 AM EDT	Special Weather Statement	PHI	Atlantic	34 min
Jul 24, 1:23 AM EDT	Special Marine Warning	PHI		97 min
Jul 24, 1:33 AM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Salem	5 hr
Jul 24, 2:02 AM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	43 min
Jul 24, 2:08 AM EDT	Special Marine Warning	PHI		97 min
Jul 24, 2:10 AM EDT	Special Marine Warning	PHI		95 min
Jul 24, 2:44 AM EDT	Special Marine Warning	PHI		91 min
Jul 24, 3:00 AM EDT	Flash Flood Warning	PHI	Burlington, Camden, Gloucester, Salem	4 hr
Jul 24, 3:03 AM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more	57 min
Jul 24, 3:17 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Warren	118 min
Jul 24, 3:21 AM EDT	Areal Flood Advisory	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	3 hr
Jul 24, 3:34 AM EDT	Special Marine Warning	PHI		116 min
Jul 24, 3:36 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset and 2 more	6 hr
Jul 24, 3:55 AM EDT	Severe Thunderstorm Warning	PHI	Burlington, Ocean	50 min
Jul 24, 9:30 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Middlesex, Morris, Somerset	60 min
Jul 24, 10:04 AM EDT	Small Craft Advisory for Hazardous Seas	PHI		8 hr
Jul 24, 10:40 AM EDT	Areal Flood Warning	PHI	Cumberland	10 hr
Jul 24, 2:55 PM EDT	Coastal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Middlesex, Monmouth, Ocean	11 hr
Jul 24, 7:07 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Warren	113 min
Jul 24, 7:48 PM EDT	Areal Flood Advisory	PHI	Hunterdon	117 min
Jul 23, 9:08 PM EDT	River Flood Warning	PHI	New Castle	17 hr
Jul 24, 1:10 AM EDT	Areal Flood Advisory	PHI	New Castle	4 hr
Jul 24, 1:52 AM EDT	Severe Thunderstorm Warning	PHI	Kent	53 min
Jul 24, 3:05 AM EDT	River Flood Warning	PHI	New Castle	8 hr
Jul 24, 4:17 AM EDT	River Flood Warning	PHI	New Castle	11 hr
Jul 24, 3:47 AM EDT	Areal Flood Advisory	PHI	Carbon, Lehigh, Monroe, Northampton	118 min
Jul 24, 5:23 PM EDT	Special Weather Statement	PHI	Berks	37 min
Jul 24, 5:31 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	59 min
Jul 24, 6:15 PM EDT	Special Weather Statement	PHI	Berks	45 min
Jul 24, 6:30 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery	60 min
Jul 24, 6:43 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh, Northampton	4 hr
Jul 24, 6:47 PM EDT	Flash Flood Warning	PHI	Berks	4 hr
Jul 24, 7:07 PM EDT	Special Weather Statement	PHI	Berks	23 min
Jul 24, 7:12 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	2 hr
Jul 24, 7:16 PM EDT	Areal Flood Advisory	PHI	Berks, Montgomery	119 min
Jul 24, 7:23 PM EDT	Flash Flood Warning	PHI	Bucks, Lehigh, Montgomery	4 hr
Jul 24, 7:26 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Montgomery	49 min
Jul 24, 7:42 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Montgomery	2 hr
Jul 24, 7:50 PM EDT	Severe Thunderstorm Warning	PHI	Montgomery, Philadelphia	25 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2017 Severe Thunderstorm Warnings in Delaware, 2017 Severe Thunderstorm Warnings in Pennsylvania, 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.