Alert archive / Pennsylvania / Tornado Warnings in 2023

Tornado Warning 30, NWS Philadelphia/Mount Holly

August 7, 2023Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Aug 7, 2023, 6:08 PM EDT for Chester County, Pennsylvania. It was in force for 19 min. 3 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
Aug 7, 2023, 6:08 PM EDT (22:08 UTC)
Expired
Aug 7, 2023, 6:27 PM EDT
In force
19 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Chester County, PA

The radar

The Philadelphia radar (KDIX), 113 km from the middle of the area, began a volume at 22:08 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

TimeReportWhereRemark
Aug 7, 6:15 PM EDTFUNNEL CLOUDCoatesville, PAEM reported funnel cloud near Coatesville.
Aug 7, 6:32 PM EDTTSTM WND GST 681 Nnw Uwchlan Twp, PA68 MPH gust measured by trained spotter. Time given in report.
Aug 7, 6:32 PM EDTTSTM WND GST 681 Nnw Uwchlan Twp, PA68 MPH gust measured by trained spotter. Time given in report.

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.

IssuedProductOfficeLasted
Aug 7, 3:13 PM EDTTornado WatchSPC8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.1 hours before the alert went out and 183 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-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2023-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 285 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2023-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
285 J/kg
Mixed-layer CIN
-147 J/kg
Mixed-layer LCL
738 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

346 
WFUS51 KPHI 072208
TORPHI
PAC029-072245-
/O.NEW.KPHI.TO.W.0030.230807T2208Z-230807T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
608 PM EDT Mon Aug 7 2023

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Central Chester County in southeastern Pennsylvania...

* Until 645 PM EDT.
    
* At 608 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Coatesville, or 12 miles west of West Chester,
  moving northeast at 50 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  West Chester, Phoenixville, Coatesville, Downingtown, Paoli,
  Chester Springs, Pughtown, Lionville, Marshallton,
  Lionville-Marchwood, West Goshen, Malvern, South Coatesville,
  Modena, Exton, Thorndale, Chesterbrook and Devon-Berwyn.

This includes Pennsylvania Turnpike between mile markers 308 and 323.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3986 7586 3989 7592 4021 7563 4004 7541
TIME...MOT...LOC 2208Z 227DEG 43KT 3992 7583 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

RCM
2 follow-up statements
989 
WWUS51 KPHI 072217
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
617 PM EDT Mon Aug 7 2023

PAC029-072245-
/O.CON.KPHI.TO.W.0030.000000T0000Z-230807T2245Z/
Chester PA-
617 PM EDT Mon Aug 7 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM EDT FOR
NORTHEASTERN CHESTER COUNTY...
    
At 617 PM EDT, a severe thunderstorm capable of producing a tornado
was located over Downingtown, or near West Chester, moving northeast
at 50 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Phoenixville, Coatesville, Downingtown, Pughtown, Lionville,
Lionville-Marchwood, Chester Springs, South Coatesville, Exton,
Thorndale and Chesterbrook.

This includes Pennsylvania Turnpike between mile markers 308 and 323.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3994 7576 3999 7583 4021 7563 4008 7546
TIME...MOT...LOC 2217Z 227DEG 43KT 4000 7572 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

RCM
907 
WWUS51 KPHI 072227
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
627 PM EDT Mon Aug 7 2023

PAC029-072236-
/O.CAN.KPHI.TO.W.0030.000000T0000Z-230807T2245Z/
Chester PA-
627 PM EDT Mon Aug 7 2023

...THE TORNADO WARNING FOR NORTHEASTERN CHESTER COUNTY IS
CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1100 PM EDT for southeastern
Pennsylvania.

Remember, a Severe Thunderstorm Warning still remains in effect.

LAT...LON 3994 7576 3999 7583 4021 7563 4008 7546
TIME...MOT...LOC 2226Z 227DEG 43KT 4008 7561 

$$

RCM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 5:33 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIBerks, Chester57 min
Aug 7, 5:37 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIDelaware53 min
Aug 7, 5:57 PM EDTAreal Flood AdvisoryPHIChester, Delaware79 min
Aug 7, 6:21 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIBerks, Bucks, Chester, Delaware, Montgomery, Philadelphia69 min
Aug 7, 6:29 PM EDTAreal Flood AdvisoryPHIChester, Delaware, Montgomery, Philadelphia63 min
Aug 7, 6:35 PM EDTTornado WarningPHIChester, Delaware, Montgomery, Philadelphia25 min
Aug 7, 6:45 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe45 min
Aug 7, 6:53 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Carbon, Lehigh, Monroe, Montgomery and 1 more52 min
Aug 7, 7:00 PM EDTAreal Flood AdvisoryPHIBerks, Lehigh, Montgomery, Northampton66 min
Aug 7, 7:20 PM EDTSevere Thunderstorm WarningPHIBucks58 min
Aug 7, 7:27 PM EDTSevere Thunderstorm WarningPHICarbon, Lehigh, Monroe, Northampton48 min

Nearby

Tornado Warnings in Pennsylvania, 2023Every tornado warning in 2023Tornadoes 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.