Alert archive / New Jersey / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 251, NWS Philadelphia/Mount Holly

August 24, 2020Hunterdon County, Warren County, New Jersey; Bucks County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 24, 2020, 6:14 PM EDT for Hunterdon County, Warren County, New Jersey; Bucks County, Northampton County, Pennsylvania. It was in force for 19 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 24, 2020, 6:14 PM EDT (22:14 UTC)
Expired
Aug 24, 2020, 6:33 PM EDT
In force
19 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, Bucks County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 77 km from the middle of the area, began a volume at 22:14 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.2 hours before the alert went out and 190 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, Brookhaven, NY at 12:00Z on 2020-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1431 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, Brookhaven, NY at 12:00Z on 2020-08-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 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
1431 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
807 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

069 
WUUS51 KPHI 242214
SVRPHI
NJC019-041-PAC017-095-242300-
/O.NEW.KPHI.SV.W.0251.200824T2214Z-200824T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
614 PM EDT Mon Aug 24 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Hunterdon County in northwestern New Jersey...
  Southwestern Warren County in northwestern New Jersey...
  North central Bucks County in southeastern Pennsylvania...
  Southeastern Northampton County in eastern Pennsylvania...

* Until 700 PM EDT.

* At 614 PM EDT, a severe thunderstorm was located over Springtown,
  or 7 miles south of Easton, moving southeast at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Easton, Bethlehem, Forks, Byram, Wilson, Hellertown, Flemington,
  Tinicum, New Hope, Alpha, Ferndale, Frenchtown, West Easton,
  Milford, Bloomsbury, Riegelsville, Stockton, Glendon, Pleasant
  Valley and Revere.

This includes the following highways...
 Interstate 78 in Pennsylvania between mile markers 67 and 76.
 Interstate 78 in New Jersey between mile markers 0 and 6.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 4034 7492 4034 7494 4033 7492 4029 7495
      4053 7534 4057 7537 4073 7525 4054 7478
TIME...MOT...LOC 2214Z 296DEG 26KT 4058 7525 

HAIL...<.75IN
WIND...60MPH
 
$$

SFJ
2 follow-up statements
392 
WWUS51 KPHI 242227
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
627 PM EDT Mon Aug 24 2020

NJC041-PAC095-242237-
/O.CAN.KPHI.SV.W.0251.000000T0000Z-200824T2300Z/
Warren NJ-Northampton PA-
627 PM EDT Mon Aug 24 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN WARREN AND
SOUTHEASTERN NORTHAMPTON COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4034 7492 4034 7494 4033 7492 4029 7495
      4048 7526 4065 7510 4054 7478
TIME...MOT...LOC 2227Z 296DEG 26KT 4054 7514 

$$

NJC019-PAC017-242300-
/O.CON.KPHI.SV.W.0251.000000T0000Z-200824T2300Z/
Hunterdon NJ-Bucks PA-
627 PM EDT Mon Aug 24 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR SOUTHERN HUNTERDON AND NORTH CENTRAL BUCKS COUNTIES...

At 627 PM EDT, a severe thunderstorm was located over Revere, or 11
miles southeast of Easton, moving southeast at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Byram, Flemington, Tinicum, New Hope, Ferndale, Frenchtown, Milford,
Bloomsbury, Stockton, Revere, Ottsville, Sergeantsville, Pipersville,
Erwinna, Lumberville, Sand Brook and Lambertville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 4034 7492 4034 7494 4033 7492 4029 7495
      4048 7526 4065 7510 4054 7478
TIME...MOT...LOC 2227Z 296DEG 26KT 4054 7514 

HAIL...<.75IN
WIND...60MPH
 
$$

SFJ
477 
WWUS51 KPHI 242233
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
633 PM EDT Mon Aug 24 2020

NJC019-PAC017-242243-
/O.CAN.KPHI.SV.W.0251.000000T0000Z-200824T2300Z/
Hunterdon NJ-Bucks PA-
633 PM EDT Mon Aug 24 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN HUNTERDON AND NORTH
CENTRAL BUCKS COUNTIES IS CANCELLED...
                
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 has been cancelled.  However gusty winds are
still possible with this thunderstorm.

LAT...LON 4034 7492 4034 7494 4033 7492 4029 7495
      4048 7526 4065 7510 4054 7478
TIME...MOT...LOC 2232Z 296DEG 26KT 4052 7509 

$$

SFJ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 23, 9:10 PM EDTSpecial Marine WarningPHI40 min
Aug 23, 9:30 PM EDTSpecial Weather StatementPHIGloucester30 min
Aug 24, 3:34 PM EDTSpecial Weather StatementPHISomerset26 min
Aug 24, 4:38 PM EDTSevere Thunderstorm WarningPHIWarren37 min
Aug 24, 5:57 PM EDTSpecial Weather StatementPHIMiddlesex33 min
Aug 24, 6:10 PM EDTSpecial Weather StatementPHIHunterdon35 min
Aug 24, 6:38 PM EDTSpecial Weather StatementPHIHunterdon, Somerset37 min
Aug 23, 8:20 PM EDTSpecial Weather StatementPHIChester25 min
Aug 23, 8:42 PM EDTSevere Thunderstorm WarningPHIChester, Delaware48 min
Aug 24, 1:15 PM EDTSevere Thunderstorm WarningPHICarbon, Lehigh, Monroe, Northampton21 min
Aug 24, 1:48 PM EDTSpecial Weather StatementPHINorthampton27 min
Aug 24, 2:20 PM EDTSpecial Weather StatementPHINorthampton25 min
Aug 24, 4:05 PM EDTAreal Flood AdvisoryPHICarbon, Monroe2 hr
Aug 24, 4:08 PM EDTSpecial Weather StatementPHIMonroe37 min
Aug 24, 5:01 PM EDTSpecial Weather StatementPHICarbon29 min
Aug 24, 5:11 PM EDTSpecial Weather StatementPHINorthampton34 min
Aug 24, 5:40 PM EDTSpecial Weather StatementPHINorthampton35 min
Aug 24, 6:05 PM EDTSpecial Weather StatementPHIBerks25 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2020Severe Thunderstorm Warnings in Pennsylvania, 2020Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.