Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 293, NWS Philadelphia/Mount Holly

August 13, 20237 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 13, 2023, 12:24 AM EDT for 7 counties in Pennsylvania. It was in force for 51 min. 17 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 13, 2023, 12:24 AM EDT (04:24 UTC)
Expired
Aug 13, 2023, 1:15 AM EDT
In force
51 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Lehigh County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 95 km from the middle of the area, began a volume at 04:25 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 13, 12:27 AM EDTTSTM WND DMGStowe, PAMultiple trees reported down in Stowe. Time estimated from radar.
Aug 13, 12:28 AM EDTTSTM WND DMG2 Ne West Pottsgrove Tw, PAMultiple trees reported down in Upper Pottsgrove Township. Time estimated from radar.
Aug 13, 12:28 AM EDTTSTM WND DMG2 Nnw Bechtelsville, PALarge tree down which also brought down wires on Groff Road at Merkle Road in District Township. Photo received on social media. Time estimated from radar.
Aug 13, 12:28 AM EDTTSTM WND DMGPottstown, PAReport from mPING: 3-inch tree limbs broken; Power poles broken. Time estimated from radar.
Aug 13, 12:29 AM EDTTSTM WND DMG2 Nne Gilbertsville, PAMultiple trees down across Douglass Township. Time estimated from radar.
Aug 13, 12:29 AM EDTTSTM WND DMGPottstown, PAMultiple trees reported down in Pottstown. Time estimated from radar.
Aug 13, 12:30 AM EDTTSTM WND DMG1 Wnw Washington Twp, PATrees down in Barto. Time estimated from radar.
Aug 13, 12:31 AM EDTTSTM WND DMGBally, PATrees down. Time estimated from radar.
Aug 13, 12:34 AM EDTTSTM WND DMG1 Ne New Hanover Twp, PAMultiple trees down across New Hanover Township. Time estimated from radar.
Aug 13, 12:35 AM EDTTSTM WND DMG3 Nw Trappe, PADown tree in wires on West Ridge Pike at Swamp Pike. Time estimated from radar.
Aug 13, 12:37 AM EDTTSTM WND DMG1 N Marlborough Twp, PASeveral trees down across Geryville Pike near Hoppenville Road. Picture sent in via Facebook. Time estimated from radar.
Aug 13, 12:37 AM EDTTSTM WND DMGGreen Lane, PADown tree in wires on Gravel Pike. Time estimated from radar.
Aug 13, 12:37 AM EDTTSTM WND DMGGreen Lane, PATree down at Hoppenville Road and Lumber Street. Time estimated from radar.
Aug 13, 12:46 AM EDTTSTM WND DMG1 Ssw West Rockhill Twp, PAMultiple trees down in West Rockhill Township. Time estimated from radar.
Aug 13, 12:47 AM EDTTSTM WND DMG1 Ese Souderton, PAReport from mPING: 1-inch tree limbs broken; Shingles blown off. Time estimated from radar.
Aug 13, 12:50 AM EDTTSTM WND DMG1 Wsw Montgomeryville, PAA 70 foot white pine tree was uprooted near the corner of Pecan Drive and Lansdale Ave in Lansdale. Photos received via social media. Time estimated from radar.
Aug 13, 1:00 AM EDTTSTM WND DMG1 Wsw Bedminster, PAMultiple trees reported down in Bedminster Township. 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 00:00Z, 4.4 hours before the alert went out and 223 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 00:00Z on 2023-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1089 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 00:00Z on 2023-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 118 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
1089 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
1619 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
118 m²/s²
0-3 km storm-relative helicity
168 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.9

Open this sounding in Storm Lab

The text

As transmitted.

794 
WUUS51 KPHI 130424
SVRPHI
PAC011-017-029-045-077-091-101-130515-
/O.NEW.KPHI.SV.W.0293.230813T0424Z-230813T0515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1224 AM EDT Sun Aug 13 2023

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southeastern Berks County in eastern Pennsylvania...
  Southeastern Lehigh County in eastern Pennsylvania...
  Montgomery County in southeastern Pennsylvania...
  Bucks County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...
  Northeastern Delaware County in southeastern Pennsylvania...

* Until 115 AM EDT.

* At 1224 AM EDT, severe thunderstorms were located along a line
  extending from near Fleetwood to near Birdsboro to near Terre Hill,
  moving east at 55 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Bensalem, Ewing, Norristown, Pottstown, Phoenixville,
  Lansdale, West Norriton, East Norriton, Yeadon, Emmaus, Quakertown,
  Perkasie, Doylestown, Byram, Conshohocken, Hatboro, Souderton,
  Bedminster and Ambler.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 295 and 356.
 Northeast Extension between mile markers 21 and 51.
 Interstate 95 in Pennsylvania between mile markers 22 and 23, and
near mile marker 27.
 Interstate 76 in Pennsylvania between mile markers 327 and 347.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 476 in Pennsylvania between mile markers 7 and 19.
 Interstate 176 in Pennsylvania between mile markers 1 and 6.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4033 7579 4055 7595 4049 7506 4042 7506
      4040 7496 4033 7494 4030 7487 4019 7479
      3992 7520 4007 7593 4011 7594 4014 7588
      4020 7598
TIME...MOT...LOC 0424Z 280DEG 46KT 4049 7586 4033 7574 4015 7600 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RCM
4 follow-up statements
337 
WWUS51 KPHI 130433
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1233 AM EDT Sun Aug 13 2023

PAC011-017-029-045-077-091-101-130515-
/O.CON.KPHI.SV.W.0293.000000T0000Z-230813T0515Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-Chester PA-Philadelphia PA-
Delaware PA-
1233 AM EDT Sun Aug 13 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 AM EDT
FOR SOUTHEASTERN BERKS...SOUTHEASTERN LEHIGH...MONTGOMERY...BUCKS...
NORTHEASTERN CHESTER...NORTHERN PHILADELPHIA AND NORTHERN DELAWARE
COUNTIES...

At 1233 AM EDT, severe thunderstorms were located along a line
extending from Lyons to Gilbertsville to near Elverson, moving east
at 55 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Philadelphia, Bensalem, Ewing, Norristown, Pottstown, Phoenixville,
Lansdale, West Norriton, East Norriton, Emmaus, Quakertown, Perkasie,
Doylestown, Byram, Conshohocken, Hatboro, Souderton, Bedminster,
Ambler and Birdsboro.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 308, and between
mile markers 316 and 355.
 Northeast Extension between mile markers 21 and 51.
 Interstate 95 in Pennsylvania near mile marker 27.
 Interstate 76 in Pennsylvania between mile markers 327 and 341.
 Interstate 476 in Pennsylvania between mile markers 12 and 19.
 Interstate 176 in Pennsylvania between mile markers 1 and 5.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4031 7568 4054 7584 4049 7506 4042 7506
      4040 7496 4033 7494 4030 7487 4019 7479
      3997 7513 4011 7583 4013 7589 4014 7588
      4020 7597
TIME...MOT...LOC 0433Z 280DEG 46KT 4047 7574 4031 7562 4013 7588 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

RCM
928 
WWUS51 KPHI 130441
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1241 AM EDT Sun Aug 13 2023

PAC045-130451-
/O.CAN.KPHI.SV.W.0293.000000T0000Z-230813T0515Z/
Delaware PA-
1241 AM EDT Sun Aug 13 2023

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN DELAWARE COUNTY IS
CANCELLED...

The storms which prompted the warning have moved north of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 4035 7563 4053 7568 4049 7506 4042 7506
      4040 7496 4033 7494 4030 7487 4019 7479
      4006 7499 4014 7546 4017 7559 4019 7578
      4022 7574
TIME...MOT...LOC 0441Z 276DEG 48KT 4050 7555 4034 7543 4021 7555 

$$

PAC011-017-029-077-091-101-130515-
/O.CON.KPHI.SV.W.0293.000000T0000Z-230813T0515Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-Chester PA-Philadelphia PA-
1241 AM EDT Sun Aug 13 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 AM EDT
FOR SOUTHEASTERN BERKS...SOUTHEASTERN LEHIGH...MONTGOMERY...BUCKS...
NORTHEASTERN CHESTER AND NORTHEASTERN PHILADELPHIA COUNTIES...

At 1241 AM EDT, severe thunderstorms were located along a line
extending from near Zionsville to Green Lane to near Royersford,
moving east at 55 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Philadelphia, Bensalem, Ewing, Norristown, Pottstown, Phoenixville,
Lansdale, West Norriton, East Norriton, Emmaus, Quakertown, Perkasie,
Doylestown, Byram, Hatboro, Souderton, Bedminster, Ambler,
Collegeville and Royersford.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 334 and 356.
 Northeast Extension between mile markers 21 and 51.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4035 7563 4053 7568 4049 7506 4042 7506
      4040 7496 4033 7494 4030 7487 4019 7479
      4006 7499 4014 7546 4017 7559 4019 7578
      4022 7574
TIME...MOT...LOC 0441Z 276DEG 48KT 4050 7555 4034 7543 4021 7555 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

RCM
950 
WWUS51 KPHI 130454
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1254 AM EDT Sun Aug 13 2023

PAC011-029-077-130504-
/O.CAN.KPHI.SV.W.0293.000000T0000Z-230813T0515Z/
Berks PA-Lehigh PA-Chester PA-
1254 AM EDT Sun Aug 13 2023

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BERKS...
SOUTHEASTERN LEHIGH AND NORTHEASTERN CHESTER COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 4006 7499 4014 7546 4016 7550 4016 7553
      4020 7555 4020 7557 4039 7555 4043 7550
      4042 7549 4051 7538 4049 7507 4042 7506
      4040 7496 4033 7494 4030 7487 4019 7479
TIME...MOT...LOC 0454Z 280DEG 46KT 4048 7538 4032 7527 4019 7539 

$$

PAC017-091-101-130515-
/O.CON.KPHI.SV.W.0293.000000T0000Z-230813T0515Z/
Montgomery PA-Bucks PA-Philadelphia PA-
1254 AM EDT Sun Aug 13 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 AM EDT
FOR MONTGOMERY...BUCKS AND NORTHEASTERN PHILADELPHIA COUNTIES...

At 1254 AM EDT, severe thunderstorms were located along a line
extending from near Quakertown to Fricks to near East Norriton,
moving east at 55 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Philadelphia, Bensalem, Ewing, Norristown, Lansdale, West Norriton,
East Norriton, Quakertown, Perkasie, Doylestown, Byram, Hatboro,
Souderton, Bedminster, Ambler, Collegeville, Royersford, Jenkintown,
Chalfont and Tinicum.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 334 and 356.
 Northeast Extension between mile markers 21 and 45.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4006 7499 4014 7546 4016 7550 4016 7553
      4020 7555 4020 7557 4039 7555 4043 7550
      4042 7549 4051 7538 4049 7507 4042 7506
      4040 7496 4033 7494 4030 7487 4019 7479
TIME...MOT...LOC 0454Z 280DEG 46KT 4048 7538 4032 7527 4019 7539 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

RCM
930 
WWUS51 KPHI 130502
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
102 AM EDT Sun Aug 13 2023

PAC017-091-101-130515-
/O.CON.KPHI.SV.W.0293.000000T0000Z-230813T0515Z/
Montgomery PA-Bucks PA-Philadelphia PA-
102 AM EDT Sun Aug 13 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 AM EDT
FOR NORTHEASTERN MONTGOMERY...BUCKS AND NORTHEASTERN PHILADELPHIA
COUNTIES...

At 101 AM EDT, severe thunderstorms were located along a line
extending from near Quakertown to Chalfont to near East Norriton,
moving east at 55 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Philadelphia, Bensalem, Ewing, Lansdale, Quakertown, Perkasie,
Doylestown, Byram, Hatboro, Souderton, Bedminster, Ambler, Chalfont,
Tinicum, Hatfield, New Hope, Yardley, Newtown, Dublin and Langhorne.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 340 and 355.
 Northeast Extension between mile markers 24 and 41.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4009 7495 4017 7534 4022 7538 4026 7538
      4032 7539 4036 7542 4037 7543 4039 7542
      4051 7538 4049 7507 4042 7506 4040 7496
      4033 7494 4030 7487 4019 7479
TIME...MOT...LOC 0501Z 280DEG 46KT 4047 7529 4031 7518 4018 7530 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RCM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 10:01 PM EDTSpecial Weather StatementPHIMonroe44 min
Aug 12, 10:28 PM EDTSpecial Weather StatementPHISchuylkill62 min
Aug 12, 11:31 PM EDTSpecial Weather StatementPHIBerks59 min
Aug 12, 11:47 PM EDTSevere Thunderstorm WarningPHIBerks43 min
Aug 13, 12:06 AM EDTAreal Flood AdvisoryPHIBerks3 hr
Aug 13, 1:10 AM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Montgomery, Northampton50 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2023Every 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.