Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 152, NWS Philadelphia/Mount Holly

July 17, 2024Hunterdon County, Warren County, New Jersey; 6 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 2024, 7:06 PM EDT for Hunterdon County, Warren County, New Jersey; 6 counties in Pennsylvania. It was in force for 54 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
Jul 17, 2024, 7:06 PM EDT (23:06 UTC)
Expired
Jul 17, 2024, 8:00 PM EDT
In force
54 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Hunterdon County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 23:06 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
Jul 17, 7:10 PM EDTHAIL 1Spring Twp, PAReport from mPING: Quarter (1.00 in.).
Jul 17, 7:30 PM EDTTSTM WND DMGHereford Twp, PAPhoto of a large tree down blocking Spring Hill Rd. Time estimated.

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
Jul 17, 12:58 PM EDTSevere Thunderstorm WatchSPC10 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.1 hours before the alert went out and 216 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 2024-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 88 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 2024-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 square meters per square second.1939Sfc1 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
88 J/kg
Mixed-layer CIN
-120 J/kg
Mixed-layer LCL
1518 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

224 
WUUS51 KPHI 172306
SVRPHI
NJC019-041-PAC011-017-029-077-091-095-180000-
/O.NEW.KPHI.SV.W.0152.240717T2306Z-240718T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
706 PM EDT Wed Jul 17 2024

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Hunterdon County in northwestern New Jersey...
  Southwestern Warren County in northwestern New Jersey...
  Berks County in eastern Pennsylvania...
  Lehigh County in eastern Pennsylvania...
  Northwestern Montgomery County in southeastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...
  North central Chester County in southeastern Pennsylvania...
  Southern Northampton County in eastern Pennsylvania...

* Until 800 PM EDT.

* At 706 PM EDT, severe thunderstorms were located along a line
  extending from near Claussville to near Fleetwood to Adamstown,
  moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Allentown, Reading, Easton, Bethlehem, Pottstown, Forks, Emmaus,
  Wyomissing, Northampton, Quakertown, Perkasie, Wilson, Washington,
  Hellertown, Birdsboro, Kutztown, Fleetwood, Sinking Spring,
  Laureldale, and East Greenville.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 304.
 Northeast Extension between mile markers 35 and 63.
 Interstate 78 in Pennsylvania between mile markers 41 and 76.
 Interstate 78 in New Jersey between mile markers 0 and 11.
 Interstate 176 in Pennsylvania between mile markers 1 and 11.

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 these storms. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4042 7599 4065 7575 4078 7492 4052 7507
      4025 7546 4012 7579 4014 7589 4016 7591
      4032 7616
TIME...MOT...LOC 2306Z 259DEG 35KT 4058 7564 4042 7583 4026 7606 

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

$$

Staarmann
2 follow-up statements
460 
WWUS51 KPHI 172332
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
732 PM EDT Wed Jul 17 2024

NJC019-041-PAC011-017-029-077-091-095-180000-
/O.CON.KPHI.SV.W.0152.000000T0000Z-240718T0000Z/
Hunterdon NJ-Warren NJ-Berks PA-Lehigh PA-Montgomery PA-Bucks PA-
Chester PA-Northampton PA-
732 PM EDT Wed Jul 17 2024

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR NORTHWESTERN HUNTERDON...SOUTHWESTERN WARREN...SOUTHEASTERN
BERKS...SOUTHEASTERN LEHIGH...NORTHWESTERN MONTGOMERY...NORTHWESTERN
BUCKS...NORTH CENTRAL CHESTER AND SOUTHERN NORTHAMPTON COUNTIES...

At 732 PM EDT, severe thunderstorms were located along a line
extending from Old Orchard to Zionsville to near Cedarville, moving
east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Allentown, Easton, Bethlehem, Pottstown, Forks, Emmaus, Northampton,
Quakertown, Perkasie, Wilson, Washington, Hellertown, Birdsboro, East
Greenville, Harmony, Alpha, Topton, Ferndale, Hampton, and
Schwenksville.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 304.
 Northeast Extension between mile markers 35 and 63.
 Interstate 78 in Pennsylvania between mile markers 49 and 76.
 Interstate 78 in New Jersey between mile markers 0 and 11.
 Interstate 176 in Pennsylvania between mile markers 1 and 11.

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 these storms.
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.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4047 7572 4067 7563 4078 7492 4052 7507
      4025 7546 4012 7579 4014 7589 4016 7591
      4022 7600
TIME...MOT...LOC 2332Z 256DEG 37KT 4068 7527 4049 7549 4025 7573 

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

$$

Staarmann
716 
WWUS51 KPHI 172350
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
750 PM EDT Wed Jul 17 2024

NJC019-041-PAC011-017-029-077-091-095-180000-
/O.EXP.KPHI.SV.W.0152.000000T0000Z-240718T0000Z/
Hunterdon NJ-Warren NJ-Berks PA-Lehigh PA-Montgomery PA-Bucks PA-
Chester PA-Northampton PA-
750 PM EDT Wed Jul 17 2024

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN HUNTERDON...
SOUTHWESTERN WARREN...SOUTHEASTERN BERKS...SOUTHEASTERN LEHIGH...
NORTHWESTERN MONTGOMERY...NORTHWESTERN BUCKS...NORTH CENTRAL CHESTER
AND SOUTHERN NORTHAMPTON COUNTIES WILL EXPIRE AT 800 PM EDT...

The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with these thunderstorms.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
northwestern New Jersey...and eastern and 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 4047 7572 4067 7563 4078 7492 4052 7507
      4025 7546 4012 7579 4014 7589 4016 7591
      4022 7600
TIME...MOT...LOC 2350Z 259DEG 35KT 4071 7506 4052 7529 4028 7553 

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 8:13 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Middlesex, Morris, Somerset62 min
Jul 16, 8:23 PM EDTSevere Thunderstorm WarningPHIMercer, Salem67 min
Jul 16, 8:50 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester, Mercer, Monmouth and 1 more55 min
Jul 16, 9:04 PM EDTSevere Thunderstorm WarningPHIAtlantic, Camden, Cumberland, Gloucester, Salem56 min
Jul 16, 9:05 PM EDTSpecial Marine WarningPHI115 min
Jul 16, 9:07 PM EDTSevere Thunderstorm WarningPHIMercer, Middlesex, Monmouth, Somerset68 min
Jul 16, 9:10 PM EDTSpecial Marine WarningPHI2 hr
Jul 16, 9:49 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 3 more71 min
Jul 16, 9:53 PM EDTSpecial Marine WarningPHI2 hr
Jul 16, 10:50 PM EDTSpecial Marine WarningPHI115 min
Jul 16, 10:58 PM EDTSevere Thunderstorm WarningPHICape May, Cumberland, Gloucester, Salem62 min
Jul 17, 12:00 AM EDTSpecial Marine WarningPHI90 min
Jul 17, 1:28 AM EDTSpecial Marine WarningPHI62 min
Jul 17, 3:04 AM EDTSmall Craft AdvisoryPHI33 hr
Jul 17, 2:25 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren65 min
Jul 17, 3:05 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester39 min
Jul 17, 3:13 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren62 min
Jul 17, 6:40 PM EDTSevere Thunderstorm WarningPHIWarren65 min
Jul 17, 7:18 PM EDTFlash Flood WarningPHISussex, Warren2 hr
Jul 16, 8:05 PM EDTSevere Thunderstorm WarningPHIChester, Delaware70 min
Jul 17, 2:16 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery59 min
Jul 17, 5:51 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe54 min
Jul 17, 6:18 PM EDTSevere Thunderstorm WarningPHICarbon, Lehigh, Monroe57 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2024Severe Thunderstorm Warnings in New Jersey, 2024Every severe thunderstorm warning in 2024

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.