Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 240, NWS Philadelphia/Mount Holly

July 27, 2023New Castle County, Delaware; Chester County, Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 27, 2023, 6:07 PM EDT for New Castle County, Delaware; Chester County, Delaware County, Pennsylvania. It was in force for 38 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 27, 2023, 6:07 PM EDT (22:07 UTC)
Expired: Jul 27, 2023, 6:45 PM EDT
In force: 38 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

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

The radar

The Philadelphia radar (KDIX), 126 km from the middle of the area, began a volume at 22:10 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 27, 6:20 PM EDT	TSTM WND DMG	West Marlborough Twp, PA	Wires down reported at Wilson Road and Doe Run Road in West Marlborough Township. 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 27, 3:18 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.1 hours before the alert went out and 168 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: 590 J/kg
Mixed-layer CIN: -205 J/kg
Mixed-layer LCL: 1387 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 139 m²/s²
0-3 km storm-relative helicity: 127 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

896 
WUUS51 KPHI 272207
SVRPHI
DEC003-PAC029-045-272245-
/O.NEW.KPHI.SV.W.0240.230727T2207Z-230727T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
607 PM EDT Thu Jul 27 2023

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  North central New Castle County in northern Delaware...
  Central Chester County in southeastern Pennsylvania...
  Southwestern Delaware County in southeastern Pennsylvania...

* Until 645 PM EDT.

* At 607 PM EDT, a severe thunderstorm was located near Gap, or 12
  miles southeast of New Holland, moving east at 35 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, West Chester, Coatesville, Westtown, Downingtown,
  Kennett Square, Parkesburg, West Grove, Arden, Homeville,
  Cochranville, Cheyney, Talleyville, Elam, Marshallton, Ashland,
  Gradyville, Greenville, Concordville and Hockessin.

This includes Interstate 95 in Delaware between mile markers 15 and
18.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3986 7601 3987 7599 3992 7600 3994 7598
      3995 7600 4004 7594 4003 7543 3974 7551
      3985 7602
TIME...MOT...LOC 2207Z 278DEG 31KT 3994 7599 

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

$$

Staarmann

2 follow-up statements

035 
WWUS51 KPHI 272220
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
620 PM EDT Thu Jul 27 2023

DEC003-PAC029-045-272245-
/O.CON.KPHI.SV.W.0240.000000T0000Z-230727T2245Z/
New Castle DE-Chester PA-Delaware PA-
620 PM EDT Thu Jul 27 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM EDT
FOR NORTH CENTRAL NEW CASTLE...CENTRAL CHESTER AND SOUTHWESTERN
DELAWARE COUNTIES...

At 620 PM EDT, a severe thunderstorm was located near Coatesville, or
11 miles west of West Chester, moving east at 35 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, West Chester, Coatesville, Westtown, Downingtown, Kennett
Square, West Grove, Arden, Cheyney, Talleyville, Elam, Marshallton,
Ashland, Gradyville, Concordville, Greenville, Hockessin, West
Goshen, Chester Heights and South Coatesville.

This includes Interstate 95 in Delaware between mile markers 17 and
19.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3984 7591 4002 7588 4001 7544 3976 7550
TIME...MOT...LOC 2220Z 277DEG 33KT 3992 7581 

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

$$

Staarmann

356 
WWUS51 KPHI 272234
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
634 PM EDT Thu Jul 27 2023

DEC003-PAC029-045-272245-
/O.CON.KPHI.SV.W.0240.000000T0000Z-230727T2245Z/
New Castle DE-Chester PA-Delaware PA-
634 PM EDT Thu Jul 27 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM EDT
FOR NORTH CENTRAL NEW CASTLE...SOUTHEASTERN CHESTER AND SOUTHWESTERN
DELAWARE COUNTIES...

At 634 PM EDT, a severe thunderstorm was located near Marshallton, or
near West Chester, moving east at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
West Chester, Westtown, Downingtown, Kennett Square, Arden,
Gradyville, Cheyney, Talleyville, Elam, Marshallton, Concordville,
West Goshen, Chester Heights and Ardentown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3985 7575 4000 7573 4000 7544 3978 7550
TIME...MOT...LOC 2234Z 278DEG 31KT 3990 7565 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 27, 3:01 AM EDT	Excessive Heat Warning	PHI	New Castle	43 hr
Jul 27, 3:07 PM EDT	Heat Advisory	PHI	New Castle	53 hr
Jul 27, 5:40 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	65 min
Jul 27, 6:32 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	58 min
Jul 27, 6:38 PM EDT	Special Weather Statement	PHI	Delaware	37 min
Jul 27, 7:22 PM EDT	Special Weather Statement	PHI	Northampton	38 min

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.