Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 35, NWS Philadelphia/Mount Holly

May 6, 2025Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 6, 2025, 1:31 PM EDT for Chester County, Pennsylvania. It was in force for 44 min. 2 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
May 6, 2025, 1:31 PM EDT (17:31 UTC)
Expired
May 6, 2025, 2:15 PM EDT
In force
44 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 Philadelphia radar (KDIX), 118 km from the middle of the area, began a volume at 17:33 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
May 6, 1:43 PM EDTTSTM WND DMG2 W East Marlborough Tw, PAReport of a large tree down blocking the roadway near the intersection of Upland Road and Byrd Road in Marlborough Twp. Time estimated from radar.
May 6, 2:05 PM EDTHAIL 0.25Exton, PAPea sized hail.

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
May 6, 1:06 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 5.5 hours before the alert went out and 181 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 2025-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 42 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 2025-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.19395878Sfc1 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
42 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
686 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
156 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

924 
WUUS51 KPHI 061731
SVRPHI
PAC029-061815-
/O.NEW.KPHI.SV.W.0035.250506T1731Z-250506T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
131 PM EDT Tue May 6 2025

The National Weather Service in Mount Holly NJ has issued a

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

* Until 215 PM EDT.

* At 131 PM EDT, a severe thunderstorm was located over West Grove,
  or 10 miles north of Newark, moving north 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...
  Exton, Elverson, South Coatesville, Modena, Coatesville, Glenmoore,
  Thorndale, West Grove, Landenberg, Chester Springs, Kennett Square,
  Toughkenamon, Lionville, Marshallton, Avondale, Kemblesville,
  Lionville-Marchwood, Downingtown, Phoenixville, and West Chester.

This includes Pennsylvania Turnpike between mile markers 300 and 319.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to large hail and 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.

&&

LAT...LON 4014 7588 4017 7582 4013 7550 3973 7577
      3972 7591
TIME...MOT...LOC 1731Z 195DEG 28KT 3982 7582 

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

$$

Staarmann
3 follow-up statements
660 
WWUS51 KPHI 061746
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
146 PM EDT Tue May 6 2025

PAC029-061815-
/O.CON.KPHI.SV.W.0035.000000T0000Z-250506T1815Z/
Chester PA-
146 PM EDT Tue May 6 2025

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR CENTRAL CHESTER COUNTY...

At 146 PM EDT, a severe thunderstorm was located near Coatesville, or
9 miles west of West Chester, moving north 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...
Exton, Elverson, South Coatesville, Modena, Coatesville, Glenmoore,
Thorndale, West Grove, Chester Springs, Kennett Square, Toughkenamon,
Lionville, Marshallton, Avondale, Lionville-Marchwood, Downingtown,
Phoenixville, and West Chester.

This includes Pennsylvania Turnpike between mile markers 300 and 319.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 4014 7588 4017 7582 4013 7550 3979 7574
      3980 7587
TIME...MOT...LOC 1746Z 195DEG 28KT 3994 7578 

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

$$

Staarmann
000 
WWUS51 KPHI 061800
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
200 PM EDT Tue May 6 2025

PAC029-061815-
/O.CON.KPHI.SV.W.0035.000000T0000Z-250506T1815Z/
Chester PA-
200 PM EDT Tue May 6 2025

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR CENTRAL CHESTER COUNTY...

At 200 PM EDT, a severe thunderstorm was located near Downingtown, or
9 miles northwest of West Chester, moving north 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...
Exton, Modena, Glenmoore, Thorndale, Chester Springs, Lionville,
Marshallton, Lionville-Marchwood, Downingtown, South Coatesville,
Phoenixville, Coatesville, and West Chester.

This includes Pennsylvania Turnpike between mile markers 302 and 319.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4017 7582 4013 7550 3993 7564 3996 7581
TIME...MOT...LOC 1800Z 195DEG 28KT 4004 7574 

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

$$

Staarmann
137 
WWUS51 KPHI 061809
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
209 PM EDT Tue May 6 2025

PAC029-061819-
/O.EXP.KPHI.SV.W.0035.000000T0000Z-250506T1815Z/
Chester PA-
209 PM EDT Tue May 6 2025

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL CHESTER COUNTY WILL
EXPIRE AT 215 PM EDT...

The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However small 
hail, gusty winds, and heavy rain are still possible with this 
thunderstorm.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
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.

LAT...LON 4017 7582 4013 7550 3993 7564 3996 7581
TIME...MOT...LOC 1809Z 195DEG 28KT 4010 7572 

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
May 6, 1:08 PM EDTSevere Thunderstorm WarningPHIBerks37 min
May 6, 2:12 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh48 min
May 6, 2:46 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh59 min
May 6, 3:41 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton49 min
May 6, 3:57 PM EDTTornado WarningPHIMonroe, Northampton33 min
May 6, 4:18 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton57 min
May 6, 4:19 PM EDTTornado WarningPHIMonroe26 min
May 6, 4:31 PM EDTTornado WarningPHIMonroe44 min
May 6, 4:44 PM EDTSevere Thunderstorm WarningPHICarbon, Lehigh, Monroe, Northampton46 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2025Every severe thunderstorm warning in 2025

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.