Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 157, NWS Philadelphia/Mount Holly

July 3, 2023Chester County, Delaware County, Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 3, 2023, 8:04 PM EDT for Chester County, Delaware County, Pennsylvania; New Castle County, Delaware. It was in force for 41 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 3, 2023, 8:04 PM EDT (00:04 UTC)
Expired: Jul 3, 2023, 8:45 PM EDT
In force: 41 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties New Castle County, DE, Chester County, PA, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 100 km from the middle of the area, began a volume at 00:04 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 3, 8:15 PM EDT	TSTM WND DMG	Hockessin, DE	Some tree limbs down. 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 3, 2:55 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.1 hours before the alert went out and 190 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: 1174 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 1237 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 66 m²/s²
0-3 km storm-relative helicity: 55 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

As transmitted.

608 
WUUS51 KPHI 040004
SVRPHI
DEC003-PAC029-045-040045-
/O.NEW.KPHI.SV.W.0157.230704T0004Z-230704T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
804 PM EDT Mon Jul 3 2023

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern New Castle County in northern Delaware...
  Southeastern Chester County in southeastern Pennsylvania...
  Central Delaware County in southeastern Pennsylvania...

* Until 845 PM EDT.

* At 803 PM EDT, a severe thunderstorm was located near Westtown, or
  near West Chester, moving northeast at 20 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...
  Wilmington, West Chester, Westtown, Kennett Square, West Grove,
  Arden, Cheyney, North Star, Talleyville, Elam, Marshallton, Lima,
  Chelsea, Radnor Township, Ashland, Gradyville, Greenville,
  Broomall, Landenberg and Paoli.

This includes the following highways...
 Interstate 95 in Pennsylvania between mile markers 0 and 1.
 Interstate 95 in Delaware between mile markers 16 and 23.
 Interstate 476 in Pennsylvania near mile marker 5, and between mile
markers 11 and 12.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3994 7583 4007 7540 4007 7537 3997 7534
      3977 7546 3973 7585
TIME...MOT...LOC 0003Z 244DEG 16KT 3990 7561 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Wunderlin

3 follow-up statements

077 
WWUS51 KPHI 040022
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
822 PM EDT Mon Jul 3 2023

DEC003-PAC029-045-040045-
/O.CON.KPHI.SV.W.0157.000000T0000Z-230704T0045Z/
New Castle DE-Chester PA-Delaware PA-
822 PM EDT Mon Jul 3 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM EDT
FOR NORTHERN NEW CASTLE...SOUTHEASTERN CHESTER AND WESTERN DELAWARE
COUNTIES...

At 822 PM EDT, a severe thunderstorm was located over Concordville,
or near West Chester, moving east at 25 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...
Wilmington, West Chester, Westtown, Kennett Square, West Grove,
Arden, Cheyney, North Star, Talleyville, Elam, Lima, Chelsea,
Ashland, Gradyville, Greenville, Landenberg, Newtown Square,
Concordville, Kemblesville and Hockessin.

This includes the following highways...
 Interstate 95 in Pennsylvania between mile markers 0 and 1.
 Interstate 95 in Delaware between mile markers 16 and 23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3989 7583 4006 7537 3990 7538 3977 7546
      3973 7585
TIME...MOT...LOC 0022Z 254DEG 21KT 3989 7552 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Wunderlin

857 
WWUS51 KPHI 040030
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
830 PM EDT Mon Jul 3 2023

DEC003-PAC029-045-040045-
/O.CON.KPHI.SV.W.0157.000000T0000Z-230704T0045Z/
New Castle DE-Chester PA-Delaware PA-
830 PM EDT Mon Jul 3 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM EDT
FOR NORTHERN NEW CASTLE...SOUTH CENTRAL CHESTER AND SOUTHWESTERN
DELAWARE COUNTIES...

At 830 PM EDT, a severe thunderstorm was located over Talleyville, or
near Wilmington, moving east at 25 mph.

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

SOURCE...Radar indicated.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, 
         siding, trees, and power lines is possible.

Locations impacted include...
Wilmington, Kennett Square, West Grove, Arden, North Star,
Talleyville, Elam, Chelsea, Ashland, Greenville, Landenberg,
Concordville, Kemblesville, Hockessin, Lima, Chester Township, Nether
Providence Township, Pike Creek, Brookhaven and Media.

This includes the following highways...
 Interstate 95 in Pennsylvania between mile markers 0 and 1.
 Interstate 95 in Delaware between mile markers 16 and 23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3985 7583 3993 7538 3990 7538 3977 7546
      3973 7585
TIME...MOT...LOC 0030Z 257DEG 23KT 3983 7555 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Wunderlin

121 
WWUS51 KPHI 040045
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
845 PM EDT Mon Jul 3 2023

DEC003-PAC029-045-040054-
/O.EXP.KPHI.SV.W.0157.000000T0000Z-230704T0045Z/
New Castle DE-Chester PA-Delaware PA-
845 PM EDT Mon Jul 3 2023

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN NEW CASTLE...SOUTH
CENTRAL CHESTER AND SOUTHWESTERN DELAWARE COUNTIES WILL EXPIRE AT 845
PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
northern Delaware...and southeastern Pennsylvania.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

Remember, a Severe Thunderstorm Warning still remains in effect for
Northern New Castle County DE

LAT...LON 3985 7583 3993 7538 3990 7538 3977 7546
      3973 7585
TIME...MOT...LOC 0044Z 244DEG 16KT 3986 7548 

$$

Wunderlin

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 3, 8:04 PM EDT	Areal Flood Advisory	PHI	Chester	35 min
Jul 3, 8:39 PM EDT	Flash Flood Warning	PHI	Chester	5 hr
Jul 3, 8:41 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	49 min
Jul 3, 9:07 PM EDT	Flash Flood Warning	PHI	Chester	5 hr
Jul 4, 4:59 PM EDT	Severe Thunderstorm Warning	PHI	Philadelphia	46 min
Jul 4, 6:30 PM EDT	Areal Flood Advisory	PHI	Philadelphia	3 hr
Jul 4, 6:53 PM EDT	Special Weather Statement	PHI	Delaware	37 min
Jul 4, 7:05 PM EDT	Areal Flood Advisory	PHI	Delaware, Philadelphia	2 hr
Jul 3, 8:31 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	3 hr
Jul 3, 8:37 PM EDT	Special Weather Statement	PHI	Sussex	23 min
Jul 3, 9:25 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	35 min
Jul 3, 10:48 PM EDT	River Flood Warning	PHI	New Castle	4 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2023 Severe Thunderstorm Warnings in Delaware, 2023 Every severe thunderstorm warning in 2023

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.