Alert archive / Pennsylvania / Tornado Warnings in 2020

Tornado Warning 7, NWS Philadelphia/Mount Holly

August 2, 2020Berks County, Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Aug 2, 2020, 6:56 AM EDT for Berks County, Lehigh County, Pennsylvania. It was in force for 34 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
Aug 2, 2020, 6:56 AM EDT (10:56 UTC)
Expired
Aug 2, 2020, 7:30 AM EDT
In force
34 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Berks County, PA, Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 117 km from the middle of the area, began a volume at 10:56 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, 7:08 AM EDTTSTM WND DMG1 S Ancient Oaks, PADOWNED TREES AND WIRES NEAR ASTER ROAD. TIME ESTIMATED FROM RADAR.
Aug 2, 7:21 AM EDTTSTM WND DMG1 E Emmaus, PADOWNED TREES AND WIRES NEAR CHESTNUT HILL ROAD IN EMMAUS. 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, 10.9 hours before the alert went out and 231 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 2020-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 878 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 2020-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 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
878 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
1054 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted.

476 
WFUS51 KPHI 021056
TORPHI
PAC011-077-021130-
/O.NEW.KPHI.TO.W.0007.200802T1056Z-200802T1130Z/

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

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Northeastern Berks County in eastern Pennsylvania...
  Southeastern Lehigh County in eastern Pennsylvania...

* Until 730 AM EDT.
    
* At 655 AM EDT, a severe thunderstorm capable of producing a tornado
  was located over Topton, or 14 miles southwest 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...
  Allentown, Emmaus, Topton, Ancient Oaks, Zionsville, Macungie and
  Alburtis.

This includes the following highways...
 Northeast Extension between mile markers 47 and 56.
 Interstate 78 in Pennsylvania between mile markers 55 and 58.

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.

&&

LAT...LON 4049 7574 4060 7551 4047 7542 4047 7543
      4043 7570
TIME...MOT...LOC 1055Z 245DEG 15KT 4047 7570 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

JEO
2 follow-up statements
134 
WWUS51 KPHI 021105
SVSPHI

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

PAC011-077-021130-
/O.CON.KPHI.TO.W.0007.000000T0000Z-200802T1130Z/
Berks PA-Lehigh PA-
705 AM EDT Sun Aug 2 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 AM EDT FOR EASTERN
BERKS AND SOUTHEASTERN LEHIGH COUNTIES...
    
At 705 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Topton, or 11 miles southwest 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...
Allentown, Emmaus, Ancient Oaks, Zionsville, Macungie and Alburtis. 

This includes the following highways...
 Northeast Extension between mile markers 47 and 55.
 Interstate 78 in Pennsylvania between mile markers 56 and 58.

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.

&&

LAT...LON 4049 7568 4060 7551 4047 7542 4047 7543
      4044 7566
TIME...MOT...LOC 1105Z 245DEG 15KT 4049 7565 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

JEO
314 
WWUS51 KPHI 021126
SVSPHI

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

PAC011-077-021136-
/O.EXP.KPHI.TO.W.0007.000000T0000Z-200802T1130Z/
Berks PA-Lehigh PA-
726 AM EDT Sun Aug 2 2020

...THE TORNADO WARNING FOR EASTERN BERKS AND SOUTHEASTERN LEHIGH
COUNTIES WILL EXPIRE AT 730 AM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 4049 7568 4060 7551 4047 7542 4047 7543
      4044 7566
TIME...MOT...LOC 1126Z 245DEG 15KT 4053 7555 

$$

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, 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, 7:39 AM EDTTornado WarningPHIBucks, Lehigh, Northampton36 min
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.