Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 67, NWS Philadelphia/Mount Holly

June 16, 2023Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 16, 2023, 10:48 AM EDT for Chester County, Pennsylvania. It was in force for 42 min. 11 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 16, 2023, 10:48 AM EDT (14:48 UTC)
Expired: Jun 16, 2023, 11:30 AM EDT
In force: 42 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Chester County, PA

The radar

The Dover AFB radar (KDOX), 121 km from the middle of the area, began a volume at 14:52 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 16, 11:10 AM EDT	TORNADO	3 Wnw West Caln Twp, PA	An EF-1 tornado began in West Caln Township near Baldwin Road where a hardwood tree was uprooted and found hanging on top of downed wires. South of here, between Baldwin Road and Chantry Lane, another hardwood tree was found snapped at its trunk. This was the
Jun 16, 11:15 AM EDT	TSTM WND DMG	West Caln Twp, PA	Pictures on social media shows numerous tree damage including some trees on power lines in parts of West Caln Township. Time estimated from radar.
Jun 16, 11:15 AM EDT	TSTM WND DMG	West Caln Twp, PA	Pictures on social media shows numerous tree damage including some trees on power lines in parts of West Caln Township. Time estimated from radar.
Jun 16, 11:15 AM EDT	TSTM WND GST 44	1 W Valley Twp, PA	AWOS station KMQS Coatesville.
Jun 16, 11:15 AM EDT	TSTM WND GST 44	1 W Valley Twp, PA	AWOS station KMQS Coatesville.
Jun 16, 11:20 AM EDT	TSTM WND DMG	Wagontown, PA	Downed tree in wires on Hibernia Road. Time estimated from radar.
Jun 16, 11:20 AM EDT	TSTM WND DMG	Wagontown, PA	Downed tree in wires on Hibernia Road. Time estimated from radar.
Jun 16, 11:20 AM EDT	TSTM WND GST 44	2 E Londonderry Twp, PA	Mesonet station DSCR White Clay Creek West Grove-SECCRA.
Jun 16, 11:20 AM EDT	TSTM WND GST 44	2 E Londonderry Twp, PA	Mesonet station DSCR White Clay Creek West Grove-SECCRA.
Jun 16, 11:22 AM EDT	TSTM WND DMG	West Brandywine Twp, PA	Severe trees with branches twisted off about 10 feet above the ground with numerous other trees down. Time estimated from radar.
Jun 16, 11:22 AM EDT	TSTM WND DMG	West Brandywine Twp, PA	Severe trees with branches twisted off about 10 feet above the ground with numerous other trees down. Time estimated from radar.

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, 2.8 hours before the alert went out and 159 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: 119 J/kg
Mixed-layer CIN: -101 J/kg
Mixed-layer LCL: 910 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 101 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

483 
WUUS51 KPHI 161448
SVRPHI
PAC029-161530-
/O.NEW.KPHI.SV.W.0067.230616T1448Z-230616T1530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1048 AM EDT Fri Jun 16 2023

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern Chester County in southeastern Pennsylvania...

* Until 1130 AM EDT.

* At 1048 AM EDT, a severe thunderstorm was located over Wakefield,
  or 15 miles north of Havre De Grace, moving east at 30 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...
  Coatesville, Oxford, Parkesburg, West Grove, Homeville, Glen Roy,
  Cochranville, Landenberg, Mount Vernon, Kemblesville, North Star,
  Hockessin, Atglen, South Coatesville, Avondale, Modena and
  Toughkenamon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3976 7606 3981 7603 3983 7604 3983 7602
      3985 7602 3987 7599 3997 7599 4004 7593
      4006 7583 3979 7571 3977 7575 3972 7578
      3972 7613
TIME...MOT...LOC 1448Z 257DEG 28KT 3977 7615 

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

$$

MLB

2 follow-up statements

765 
WWUS51 KPHI 161455
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1055 AM EDT Fri Jun 16 2023

PAC029-161530-
/O.CON.KPHI.SV.W.0067.000000T0000Z-230616T1530Z/
Chester PA-
1055 AM EDT Fri Jun 16 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 AM EDT
FOR SOUTHWESTERN CHESTER COUNTY...

At 1055 AM EDT, a severe thunderstorm was located over Glen Roy, or
16 miles north of Havre De Grace, moving east at 30 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...
Coatesville, Oxford, Parkesburg, West Grove, Homeville, Glen Roy,
Cochranville, Landenberg, Mount Vernon, Kemblesville, North Star,
Hockessin, Atglen, South Coatesville, Avondale, Modena and
Toughkenamon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 3976 7606 3981 7603 3983 7604 3983 7602
      3985 7602 3987 7599 3997 7599 4004 7593
      4006 7583 3979 7571 3977 7575 3972 7578
      3972 7613
TIME...MOT...LOC 1455Z 257DEG 28KT 3978 7608 

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

$$

MLB

023 
WWUS51 KPHI 161514
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1114 AM EDT Fri Jun 16 2023

PAC029-161530-
/O.CON.KPHI.SV.W.0067.000000T0000Z-230616T1530Z/
Chester PA-
1114 AM EDT Fri Jun 16 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 AM EDT
FOR SOUTHWESTERN CHESTER COUNTY...

At 1113 AM EDT, a severe thunderstorm was located near West Grove, or
11 miles northwest of Newark, moving east at 30 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...
Coatesville, Oxford, Parkesburg, West Grove, Homeville, Glen Roy,
Cochranville, Landenberg, Mount Vernon, Kemblesville, North Star,
Hockessin, Atglen, South Coatesville, Avondale, Modena and
Toughkenamon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 3976 7606 3981 7603 3983 7604 3983 7602
      3985 7602 3987 7599 3997 7599 4004 7593
      4006 7583 3979 7571 3977 7575 3972 7578
      3972 7613
TIME...MOT...LOC 1513Z 257DEG 28KT 3981 7590 

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

$$

MLB

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 16, 10:26 AM EDT	Special Weather Statement	PHI	Chester	34 min
Jun 16, 11:02 AM EDT	Special Weather Statement	PHI	Delaware	28 min
Jun 16, 11:10 AM EDT	Tornado Warning	PHI	Berks, Chester	35 min
Jun 16, 11:20 AM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Delaware, Montgomery	40 min
Jun 16, 11:33 AM EDT	Tornado Warning	PHI	Chester, Delaware, Montgomery	27 min
Jun 16, 11:46 AM EDT	Severe Thunderstorm Warning	PHI	Delaware, Philadelphia	59 min
Jun 16, 11:58 AM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	47 min
Jun 16, 12:41 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	49 min
Jun 16, 12:46 PM EDT	Areal Flood Advisory	PHI	Bucks, Delaware, Montgomery, Philadelphia	3 hr
Jun 16, 12:49 PM EDT	Flash Flood Warning	PHI	Bucks, Philadelphia	3 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 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.