Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 123, NWS Philadelphia/Mount Holly

July 6, 2020Hunterdon County, Warren County, New Jersey; Bucks County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 6, 2020, 3:38 PM EDT for Hunterdon County, Warren County, New Jersey; Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 52 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 6, 2020, 3:38 PM EDT (19:38 UTC)
Expired
Jul 6, 2020, 4:30 PM EDT
In force
52 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Hunterdon County, NJ, Warren County, NJ, Bucks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 98 km from the middle of the area, began a volume at 19:38 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 6, 3:40 PM EDTTSTM WND DMG2 Sse Hellertown, PAAN MPING REPORT OF 3 INCH DIAMETER TREE LIMBS OR POWER POLES SNAPPED. TIME ESTIMATED FROM RADAR.
Jul 6, 3:40 PM EDTHAIL 1.25Center Valley, PAREPORT VIA SOCIAL MEDIA WITH PHOTO OF HAIL TO HALF DOLLAR SIZE OR A LITTLE LARGER. TIME ESTIMATED FROM RADAR.

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 6, 1:38 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.6 hours before the alert went out and 204 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 2020-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 100 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 2020-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 39 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
100 J/kg
Mixed-layer CIN
-192 J/kg
Mixed-layer LCL
1959 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

936 
WUUS51 KPHI 061938
SVRPHI
NJC019-041-PAC017-077-095-062030-
/O.NEW.KPHI.SV.W.0123.200706T1938Z-200706T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
338 PM EDT Mon Jul 6 2020

The National Weather Service in Mount Holly NJ has issued a

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

* Until 430 PM EDT.

* At 338 PM EDT, severe thunderstorms were located along a line
  extending from near Hellertown to Lumberville, moving northwest at
  10 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...
  Allentown, Easton, Bethlehem, Quakertown, Byram, Bedminster,
  Hellertown, Tinicum, Ferndale, Frenchtown, Riegelsville, Stockton,
  Pleasant Valley, Revere, Lehigh University, Lumberville, Ottsville,
  Pipersville, Springtown and Erwinna.

This includes the following highways...
 Northeast Extension near mile marker 47.
 Interstate 78 in Pennsylvania between mile markers 59 and 72.

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.

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.

&&

LAT...LON 4064 7518 4038 7493 4047 7546 4065 7550
TIME...MOT...LOC 1938Z 141DEG 9KT 4054 7535 4042 7504 

HAIL...1.00IN
WIND...60MPH
 
$$

Robertson

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 6, 3:16 AM EDTHeat AdvisoryPHIBurlington, Camden, Gloucester, Mercer12 hr
Jul 6, 12:45 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden60 min
Jul 6, 12:52 PM EDTFlash Flood WatchPHIBurlington, Camden, Gloucester, Mercer, Salem8 hr
Jul 6, 12:57 PM EDTAreal Flood AdvisoryPHIBurlington, Camden2 hr
Jul 6, 1:08 PM EDTFlash Flood WarningPHIBurlington, Camden4 hr
Jul 6, 1:15 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Monmouth60 min
Jul 6, 1:43 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden62 min
Jul 6, 1:52 PM EDTSpecial Weather StatementPHIOcean23 min
Jul 6, 2:00 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean75 min
Jul 6, 2:02 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Mercer, Middlesex, Monmouth, Ocean118 min
Jul 6, 2:39 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester, Ocean66 min
Jul 6, 2:41 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer49 min
Jul 6, 2:46 PM EDTSpecial Marine WarningPHI89 min
Jul 6, 2:48 PM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Camden, Gloucester, Ocean4 hr
Jul 6, 2:51 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Monmouth39 min
Jul 6, 2:57 PM EDTFlash Flood Warning EmergencyCatastrophic damage threatPHIBurlington, Camden, Gloucester4 hr
Jul 6, 3:00 PM EDTSevere Thunderstorm WarningPHIHunterdon, Warren45 min
Jul 6, 3:14 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean46 min
Jul 6, 3:18 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Somerset42 min
Jul 6, 3:34 PM EDTAreal Flood AdvisoryPHIMiddlesex, Monmouth, Somerset116 min
Jul 6, 3:36 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Ocean54 min
Jul 6, 3:36 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset39 min
Jul 6, 3:44 PM EDTSpecial Marine WarningPHI61 min
Jul 6, 3:44 PM EDTSpecial Marine WarningPHI61 min
Jul 6, 3:47 PM EDTFlash Flood WarningPHIMiddlesex, Morris, Somerset4 hr
Jul 6, 3:47 PM EDTSevere Thunderstorm WarningPHIAtlantic, Camden, Cumberland, Gloucester, Salem58 min
Jul 6, 4:41 PM EDTSpecial Marine WarningPHI64 min
Jul 6, 4:45 PM EDTSpecial Marine WarningPHI41 min
Jul 6, 4:45 PM EDTSevere Thunderstorm WarningPHIAtlantic, Cape May, Cumberland, Salem60 min
Jul 6, 4:58 PM EDTSpecial Marine WarningPHI62 min
Jul 6, 5:24 PM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more4 hr
Jul 6, 5:39 PM EDTSpecial Marine WarningPHI66 min
Jul 6, 5:43 PM EDTSevere Thunderstorm WarningPHIAtlantic, Cape May, Cumberland47 min
Jul 6, 5:57 PM EDTSpecial Marine WarningPHI63 min
Jul 6, 6:00 PM EDTSevere Thunderstorm WarningPHISalem60 min
Jul 6, 6:43 PM EDTSpecial Marine WarningPHI44 min
Jul 6, 6:56 PM EDTSpecial Marine WarningPHI47 min
Jul 6, 7:18 PM EDTSevere Thunderstorm WarningPHISussex, Warren36 min
Jul 6, 7:55 PM EDTSpecial Weather StatementPHISussex50 min
Jul 6, 12:34 PM EDTSpecial Weather StatementPHIPhiladelphia26 min
Jul 6, 1:20 PM EDTSpecial Weather StatementPHIMontgomery25 min
Jul 6, 1:24 PM EDTSpecial Weather StatementPHIMonroe36 min
Jul 6, 1:44 PM EDTSpecial Weather StatementPHIMontgomery31 min
Jul 6, 1:50 PM EDTAreal Flood AdvisoryPHIBerks, Chester, Montgomery4 hr
Jul 6, 1:50 PM EDTSevere Thunderstorm WarningPHIMonroe40 min
Jul 6, 2:04 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery41 min
Jul 6, 2:10 PM EDTAreal Flood AdvisoryPHIMonroe2 hr
Jul 6, 2:18 PM EDTSpecial Weather StatementPHIMontgomery27 min
Jul 6, 2:27 PM EDTSevere Thunderstorm WarningPHIMontgomery48 min
Jul 6, 2:28 PM EDTSevere Thunderstorm WarningPHIMonroe28 min
Jul 6, 2:39 PM EDTAreal Flood AdvisoryPHIBucks, Chester, Montgomery4 hr
Jul 6, 2:51 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery24 min
Jul 6, 3:11 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia49 min
Jul 6, 3:52 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia38 min
Jul 6, 3:56 PM EDTSevere Thunderstorm WarningPHICarbon, Lehigh, Monroe, Northampton64 min
Jul 6, 4:06 PM EDTSevere Thunderstorm WarningPHILehigh24 min
Jul 6, 4:07 PM EDTFlash Flood WarningPHIChester, Delaware, Montgomery4 hr
Jul 6, 4:31 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Monroe, Northampton44 min
Jul 6, 4:51 PM EDTAreal Flood AdvisoryPHICarbon, Monroe114 min
Jul 6, 5:00 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton45 min
Jul 6, 5:01 PM EDTAreal Flood AdvisoryPHIBerks, Carbon, Lehigh, Monroe, Northampton119 min
Jul 6, 5:14 PM EDTSevere Thunderstorm WarningPHIChester61 min
Jul 6, 5:17 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Montgomery, Northampton43 min
Jul 6, 5:20 PM EDTSevere Thunderstorm WarningPHIChester, Delaware42 min
Jul 6, 5:29 PM EDTSevere Thunderstorm WarningPHIChester46 min
Jul 6, 5:43 PM EDTAreal Flood AdvisoryPHIChester, Delaware3 hr
Jul 6, 5:53 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery52 min
Jul 6, 6:13 PM EDTSevere Thunderstorm WarningPHIChester48 min
Jul 6, 6:14 PM EDTAreal Flood AdvisoryPHIBerks, Chester, Montgomery3 hr
Jul 6, 6:18 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery35 min
Jul 6, 6:54 PM EDTFlash Flood WarningPHIBerks, Chester, Montgomery109 min
Jul 6, 7:36 PM EDTSevere Thunderstorm WarningPHIChester69 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2020Severe Thunderstorm Warnings in New Jersey, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.