Alert archive / Pennsylvania / Tornado Warnings in 2021

Tornado Warning 52, NWS Philadelphia/Mount Holly

September 8, 2021Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Sep 8, 2021, 10:23 PM EDT for Berks County, Pennsylvania. It was in force for 22 min. 7 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
Sep 8, 2021, 10:23 PM EDT (02:23 UTC)
Expired
Sep 8, 2021, 10:45 PM EDT
In force
22 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 151 km from the middle of the area, began a volume at 02:23 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
Sep 8, 10:28 PM EDTTSTM WND DMG2 S Robesonia, PATREE AND WIRES DOWN IN SOUTH HEIDELBERG TOWNSHIP. TIME ESTIMATED FROM RADAR.
Sep 8, 10:32 PM EDTTSTM WND DMG1 Ssw Wernersville, PATREES DOWN ON PREMISES OF WERNERSVILLE STATE HOSPITAL. TIME ESTIMATED FROM RADAR.
Sep 8, 10:40 PM EDTTSTM WND DMG1 N Spring Twp, PAMULTIPLE TREES AND POWERLINES DOWN ON HOUSES AND VEHICLES.
Sep 8, 10:40 PM EDTTSTM WND DMGWest Lawn, PATREE ON GARAGE ON CLEVELAND AVENUE IN SPRING TOWNSHIP. TIME ESTIMATED FROM RADAR.
Sep 8, 10:42 PM EDTTSTM WND DMGWyomissing, PATREE DOWN ON GARAGE, TIME ESTIMATED FROM RADAR.
Sep 8, 10:43 PM EDTTSTM WND DMGBern Twp, PAMULTIPLE LARGE TREES DOWN. TIME ESTIMATED FROM RADAR.
Sep 8, 10:48 PM EDTTSTM WND DMGShillington, PATREE AND WIRES DOWN ON 601 BROBST STREET IN SHILLINGTON BOROUGH. 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
Sep 8, 7:54 PM EDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 2.4 hours before the alert went out and 193 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 2021-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1652 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 2021-09-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.19395878Sfc1 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
1652 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
1146 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
1.0
Supercell composite
7.0

Open this sounding in Storm Lab

The text

As transmitted.

340 
WFUS51 KPHI 090223
TORPHI
PAC011-090300-
/O.NEW.KPHI.TO.W.0052.210909T0223Z-210909T0300Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
1023 PM EDT Wed Sep 8 2021

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Central Berks County in eastern Pennsylvania...

* Until 1100 PM EDT.
    
* At 1022 PM EDT, a severe thunderstorm capable of producing a
  tornado was located over Womelsdorf, or near Myerstown, moving east
  at 35 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...
  Reading, Wyomissing, Sinking Spring, Laureldale, Womelsdorf,
  Wernersville, Robesonia, Leesport, Bernville, Fairview Hgts, Spring
  Ridge, Shillington, West Reading, Mohnton, Kenhorst, Wyomissing
  Hills, West Lawn, Whitfield and West Wyomissing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4040 7624 4051 7584 4027 7595 4027 7608
      4037 7623
TIME...MOT...LOC 0222Z 251DEG 31KT 4036 7618 

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

$$

JEO
2 follow-up statements
447 
WWUS51 KPHI 090233
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1033 PM EDT Wed Sep 8 2021

PAC011-090300-
/O.CON.KPHI.TO.W.0052.000000T0000Z-210909T0300Z/
Berks PA-
1033 PM EDT Wed Sep 8 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT FOR CENTRAL
BERKS COUNTY...
    
At 1033 PM EDT, a severe thunderstorm capable of producing a tornado
was located near Fairview Hgts, or 7 miles northwest of Reading,
moving east at 35 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...
Reading, Wyomissing, Sinking Spring, Laureldale, Wernersville,
Robesonia, Leesport, Bernville, Fairview Hgts, Spring Ridge,
Shillington, West Reading, Mohnton, Kenhorst, Wyomissing Hills, West
Lawn, Whitfield and West Wyomissing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 4029 7594 4030 7608 4037 7615 4042 7616
      4051 7584
TIME...MOT...LOC 0233Z 251DEG 31KT 4039 7606 

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

$$

JEO
107 
WWUS51 KPHI 090245
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1045 PM EDT Wed Sep 8 2021

PAC011-090254-
/O.CAN.KPHI.TO.W.0052.000000T0000Z-210909T0300Z/
Berks PA-
1045 PM EDT Wed Sep 8 2021

...THE TORNADO WARNING FOR CENTRAL BERKS COUNTY IS CANCELLED...
                
The rotation which prompted the warning has weakened, and no longer 
appears capable of producing a tornado. Therefore, the 
Tornado Warning has been cancelled.

However, a Severe Thunderstorm Warning still remains in effect for 
this area, and damaging straight line winds remain possible.

LAT...LON 4029 7594 4030 7608 4037 7615 4042 7616
      4051 7584
TIME...MOT...LOC 0243Z 251DEG 31KT 4042 7594 

$$

JEO

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 8, 8:47 PM EDTSpecial Weather StatementPHINorthampton28 min
Sep 8, 9:12 PM EDTSpecial Weather StatementPHILehigh48 min
Sep 8, 9:16 PM EDTAreal Flood AdvisoryPHILehigh, Northampton3 hr
Sep 8, 9:16 PM EDTSpecial Weather StatementPHINorthampton29 min
Sep 8, 9:38 PM EDTSpecial Weather StatementPHIBerks52 min
Sep 8, 9:46 PM EDTSpecial Weather StatementPHILehigh, Northampton44 min
Sep 8, 9:48 PM EDTFlash Flood WarningPHILehigh, Northampton7 hr
Sep 8, 9:59 PM EDTAreal Flood AdvisoryPHIBerks3 hr
Sep 8, 10:11 PM EDTSevere Thunderstorm WarningPHIBerks49 min
Sep 8, 10:27 PM EDTSpecial Weather StatementPHINorthampton33 min
Sep 8, 10:42 PM EDTFlash Flood WarningPHINorthampton6 hr
Sep 8, 10:47 PM EDTAreal Flood AdvisoryPHICarbon, Monroe3 hr
Sep 8, 10:47 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Montgomery, Northampton58 min
Sep 8, 10:56 PM EDTSpecial Weather StatementPHINorthampton34 min
Sep 8, 11:27 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Northampton48 min
Sep 8, 11:35 PM EDTSpecial Weather StatementPHIChester, Delaware, Montgomery40 min
Sep 9, 12:08 AM EDTSpecial Weather StatementPHIBucks, Delaware, Montgomery, Philadelphia37 min
Sep 9, 4:26 AM EDTAreal Flood WarningPHILehigh, Northampton3 hr
Sep 9, 4:28 AM EDTAreal Flood WarningPHINorthampton4 hr

Nearby

Tornado Warnings in Pennsylvania, 2021Every tornado warning in 2021Tornadoes in 2021

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.