Alert archive / Pennsylvania / Tornado Warnings in 2020

Tornado Warning 8, NWS Philadelphia/Mount Holly

August 2, 2020Bucks County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Aug 2, 2020, 7:39 AM EDT for Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 36 min. 1 report 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 2, 2020, 7:39 AM EDT (11:39 UTC)
Expired
Aug 2, 2020, 8:15 AM EDT
In force
36 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.0 in

Counties Bucks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 102 km from the middle of the area, began a volume at 11:42 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 2, 7:57 AM EDTTSTM WND DMG2 W Durham Twp, PADOWNED POWER LINES NEAR HAUPTS BRIDGE ROAD IN DURHAM TWP. 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

Brookhaven, NY (KOKX), launched 00:00Z, 11.7 hours before the alert went out and 213 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 00:00Z on 2020-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 18 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 00:00Z on 2020-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 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
18 J/kg
Mixed-layer CIN
-74 J/kg
Mixed-layer LCL
1421 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

747 
WFUS51 KPHI 021139
TORPHI
PAC017-077-095-021215-
/O.NEW.KPHI.TO.W.0008.200802T1139Z-200802T1215Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
739 AM EDT Sun Aug 2 2020

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Southeastern Lehigh County in eastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...
  South central Northampton County in eastern Pennsylvania...

* Until 815 AM EDT.
    
* At 739 AM EDT, a severe thunderstorm capable of producing a tornado
  was located near Pleasant Valley, or 7 miles southeast of
  Allentown, moving northeast at 15 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Easton, Bethlehem, Hellertown, Pleasant Valley, Springtown, Old
  Orchard, Coopersburg and Richlandtown.

This includes Interstate 78 in Pennsylvania near mile marker 64, and
between mile markers 66 and 73.
 
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.

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

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

&&

LAT...LON 4046 7543 4052 7547 4066 7527 4049 7516
TIME...MOT...LOC 1139Z 244DEG 14KT 4051 7539 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

Staarmann
2 follow-up statements
797 
WWUS51 KPHI 021152
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
752 AM EDT Sun Aug 2 2020

PAC017-077-095-021215-
/O.CON.KPHI.TO.W.0008.000000T0000Z-200802T1215Z/
Lehigh PA-Bucks PA-Northampton PA-
752 AM EDT Sun Aug 2 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 815 AM EDT FOR EAST
CENTRAL LEHIGH...NORTHWESTERN BUCKS AND SOUTH CENTRAL NORTHAMPTON
COUNTIES...
    
At 752 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Pleasant Valley, or 8 miles southeast of Allentown,
moving northeast at 15 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Easton, Bethlehem, Hellertown, Pleasant Valley, Springtown, Old
Orchard, Coopersburg and Richlandtown.

This includes Interstate 78 in Pennsylvania near mile marker 64, and
between mile markers 66 and 73.
 
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.

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

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

&&

LAT...LON 4047 7536 4055 7543 4066 7527 4049 7516
TIME...MOT...LOC 1152Z 244DEG 14KT 4053 7533 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

Staarmann
567 
WWUS51 KPHI 021207
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
807 AM EDT Sun Aug 2 2020

PAC017-077-095-021217-
/O.EXP.KPHI.TO.W.0008.000000T0000Z-200802T1215Z/
Lehigh PA-Bucks PA-Northampton PA-
807 AM EDT Sun Aug 2 2020

...THE TORNADO WARNING FOR EAST CENTRAL LEHIGH...NORTHWESTERN BUCKS
AND SOUTH CENTRAL NORTHAMPTON COUNTIES WILL EXPIRE AT 815 AM EDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.  However gusty winds and heavy rain are still
possible with this thunderstorm.

LAT...LON 4047 7536 4055 7543 4066 7527 4049 7516
TIME...MOT...LOC 1207Z 244DEG 14KT 4055 7526 

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 3:32 AM EDTAreal Flood AdvisoryPHIBerks4 hr
Aug 2, 4:42 AM EDTFlash Flood WarningPHIBerks4 hr
Aug 2, 6:30 AM EDTSevere Thunderstorm WarningPHIBerks, Lehigh45 min
Aug 2, 6:37 AM EDTTornado WarningPHIBerks, Lehigh23 min
Aug 2, 6:56 AM EDTTornado WarningPHIBerks, Lehigh34 min
Aug 2, 7:13 AM EDTAreal Flood AdvisoryPHIBerks, Lehigh, Northampton3 hr
Aug 2, 7:29 AM EDTSpecial Weather StatementPHILehigh31 min
Aug 2, 7:34 AM EDTAreal Flood AdvisoryPHIBucks, Lehigh, Northampton3 hr
Aug 2, 7:49 AM EDTAreal Flood AdvisoryPHIBerks, Carbon, Lehigh, Monroe, Northampton84 min
Aug 2, 7:54 AM EDTSpecial Weather StatementPHILehigh36 min
Aug 2, 8:24 AM EDTSpecial Weather StatementPHILehigh36 min
Aug 2, 8:28 AM EDTAreal Flood WarningPHIBerks3 hr
Aug 2, 8:46 AM EDTAreal Flood AdvisoryPHINorthampton3 hr
Aug 2, 3:33 PM EDTFlash Flood WatchPHIBerks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more48 hr
Aug 2, 5:04 PM EDTTropical Storm WatchPHIBucks, Delaware, Montgomery, Philadelphia18 hr
Aug 2, 5:14 PM EDTSpecial Weather StatementPHICarbon, Monroe31 min
Aug 2, 5:51 PM EDTSpecial Weather StatementPHILehigh, Northampton39 min
Aug 2, 6:29 PM EDTSpecial Weather StatementPHINorthampton31 min

Nearby

Tornado Warnings in Pennsylvania, 2020Every tornado warning in 2020Tornadoes 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.