Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 296, NWS Philadelphia/Mount Holly

September 8, 2021Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 8, 2021, 10:11 PM EDT for Berks County, Pennsylvania. It was in force for 49 min. 9 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, 10:11 PM EDT (02:11 UTC)
Expired
Sep 8, 2021, 11:00 PM EDT
In force
49 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 156 km from the middle of the area, began a volume at 02:14 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.

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.
Sep 8, 10:55 PM EDTTSTM WND GST 611 Ne Reading, PAWIND GUST MEASURED AT SITE EW3190 (ELEVATION 1115 FT).
Sep 8, 10:58 PM EDTTSTM WND DMG2 N Mount Penn, PATREE ON WIRES ON ANGORA ROAD IN LOWER ALSACE TOWNSHIP. 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, 2.2 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, 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°0°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.

542 
WUUS51 KPHI 090211
SVRPHI
PAC011-090300-
/O.NEW.KPHI.SV.W.0296.210909T0211Z-210909T0300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1011 PM EDT Wed Sep 8 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Berks County in eastern Pennsylvania...

* Until 1100 PM EDT.

* At 1010 PM EDT, severe thunderstorms were located along a line
  extending from near Strausstown to near Schaefferstown, moving
  northeast at 40 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...
  Reading, Wyomissing, Kutztown, Hamburg, Fleetwood, Sinking Spring,
  Laureldale, Womelsdorf, Wernersville, Robesonia, Leesport,
  Shoemakersville, Bernville, Lyons, Strausstown, Lenhartsville,
  Spring Ridge, Fairview Hgts, Shillington and West Reading.

This includes Interstate 78 in Pennsylvania near mile marker 8, and
between mile markers 10 and 41.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4052 7634 4052 7625 4058 7606 4057 7602
      4064 7598 4068 7589 4064 7584 4045 7570
      4028 7602 4027 7608 4036 7621 4040 7629
      4049 7643
TIME...MOT...LOC 0210Z 230DEG 35KT 4046 7627 4027 7633 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JEO
3 follow-up statements
932 
WWUS51 KPHI 090226
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1026 PM EDT Wed Sep 8 2021

PAC011-090300-
/O.CON.KPHI.SV.W.0296.000000T0000Z-210909T0300Z/
Berks PA-
1026 PM EDT Wed Sep 8 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR CENTRAL BERKS COUNTY...

At 1026 PM EDT, severe thunderstorms were located along a line
extending from near Strausstown to Womelsdorf, moving northeast at 40
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...
Reading, Wyomissing, Kutztown, Hamburg, Fleetwood, Sinking Spring,
Laureldale, Womelsdorf, Wernersville, Robesonia, Leesport,
Shoemakersville, Bernville, Lyons, Strausstown, Lenhartsville, Spring
Ridge, Fairview Hgts, Shillington and West Reading.

This includes Interstate 78 in Pennsylvania between mile markers 15
and 41.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4052 7625 4058 7606 4057 7602 4064 7598
      4068 7589 4064 7584 4045 7570 4028 7602
      4027 7608 4036 7621 4043 7633
TIME...MOT...LOC 0226Z 230DEG 35KT 4055 7612 4036 7618 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JEO
736 
WWUS51 KPHI 090248
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1048 PM EDT Wed Sep 8 2021

PAC011-090300-
/O.CON.KPHI.SV.W.0296.000000T0000Z-210909T0300Z/
Berks PA-
1048 PM EDT Wed Sep 8 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR CENTRAL BERKS COUNTY...

At 1048 PM EDT, severe thunderstorms were located along a line
extending from near Wanamakers to Shoemakersville, moving northeast
at 40 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Reading, Wyomissing, Kutztown, Hamburg, Fleetwood, Sinking Spring,
Laureldale, Wernersville, Leesport, Shoemakersville, Lyons,
Lenhartsville, Fairview Hgts, Spring Ridge, Shillington, West
Reading, Mohnton, Centerport, Wyomissing Hills and West Lawn.

This includes Interstate 78 in Pennsylvania between mile markers 28
and 41.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4052 7605 4058 7606 4057 7602 4064 7598
      4068 7589 4064 7584 4045 7570 4028 7602
      4027 7608 4033 7608 4040 7605
TIME...MOT...LOC 0248Z 230DEG 35KT 4068 7592 4049 7598 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JEO
652 
WWUS51 KPHI 090259
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1059 PM EDT Wed Sep 8 2021

PAC011-090307-
/O.EXP.KPHI.SV.W.0296.000000T0000Z-210909T0300Z/
Berks PA-
1059 PM EDT Wed Sep 8 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BERKS COUNTY WILL
EXPIRE AT 1100 PM EDT...
    
The storms which prompted the warning have partially moved out of 
the area. Therefore, the warning will be allowed to expire. However, 
a more recent Severe Thunderstorm Warning remains in effect for much 
of central and eastern Berks County.

A Severe Thunderstorm Watch remains in effect until midnight EDT for
eastern Pennsylvania.

LAT...LON 4052 7605 4058 7606 4057 7602 4064 7598
      4068 7589 4064 7584 4045 7570 4028 7602
      4027 7608 4033 7608 4040 7605
TIME...MOT...LOC 0257Z 230DEG 35KT 4068 7592 4049 7598 

$$

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, 10:23 PM EDTTornado WarningPHIBerks22 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

Severe Thunderstorm Warnings in Pennsylvania, 2021Every severe thunderstorm warning 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.