Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 155, NWS Philadelphia/Mount Holly

August 4, 2017Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 4, 2017, 11:36 PM EDT for Berks County, Pennsylvania. It was in force for 69 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 4, 2017, 11:36 PM EDT (03:36 UTC)
Expired
Aug 5, 2017, 12:45 AM EDT
In force
69 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 158 km from the middle of the area, began a volume at 03:36 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 5, 12:35 AM EDTTSTM WND DMGLower Heidelberg Twp, PATREE REPORTED DOWN.

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, 3.6 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, Washington/Dulle, VA at 00:00Z on 2017-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 786 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 2017-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 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
786 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1447 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
202 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.7

Open this sounding in Storm Lab

The text

As transmitted.

592 
WUUS51 KPHI 050336
SVRPHI
PAC011-050445-
/O.NEW.KPHI.SV.W.0155.170805T0336Z-170805T0445Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1136 PM EDT FRI AUG 4 2017

The National Weather Service in Mount Holly NJ has issued a

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

* Until 1245 AM EDT

* At 1135 PM EDT, severe thunderstorms were located along a line
  extending from near Fredericksburg to near Avon to near Cornwall to
  near Manheim, moving northeast at 30 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Reading, Wyomissing, Kutztown, Hamburg, Fleetwood, Sinking Spring,
  Laureldale, Womelsdorf, Wernersville, Topton, Leesport,
  Shoemakersville, Bernville, Lyons, Strausstown, Lenhartsville,
  Fairview Hgts, Spring Ridge, West Reading and Centerport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4052 7634 4052 7625 4058 7605 4057 7602
      4064 7598 4068 7589 4049 7561 4027 7607
      4036 7621 4037 7623 4049 7643
TIME...MOT...LOC 0335Z 244DEG 27KT 4049 7641 4037 7636 4025 7635 4017
7646

HAIL...<.75IN
WIND...60MPH
 
$$

Gorse
2 follow-up statements
871 
WWUS51 KPHI 050403
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1203 AM EDT SAT AUG 5 2017

PAC011-050445-
/O.CON.KPHI.SV.W.0155.000000T0000Z-170805T0445Z/
Berks PA-
1203 AM EDT SAT AUG 5 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1245 AM EDT
FOR CENTRAL BERKS COUNTY...

At 1202 AM EDT, severe thunderstorms were located along a line
extending from near McKeansburg to Shoemakersville to Wernersville to
near Denver, moving northeast at 20 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Reading, Wyomissing, Kutztown, Hamburg, Fleetwood, Sinking Spring,
Laureldale, Womelsdorf, Wernersville, Topton, Leesport,
Shoemakersville, Bernville, Lyons, Strausstown, Lenhartsville,
Fairview Hgts, Spring Ridge, West Reading and Centerport.

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
flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4052 7625 4058 7605 4057 7602 4064 7598
      4068 7589 4049 7561 4027 7607 4036 7621
      4037 7623
TIME...MOT...LOC 0402Z 230DEG 18KT 4063 7596 4048 7598 4031 7606 4024
7620

HAIL...<.75IN
WIND...60MPH
 
$$

Gorse
666 
WWUS51 KPHI 050436
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1236 AM EDT SAT AUG 5 2017

PAC011-050445-
/O.EXP.KPHI.SV.W.0155.000000T0000Z-170805T0445Z/
Berks PA-
1236 AM EDT SAT AUG 5 2017

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BERKS COUNTY WILL
EXPIRE AT 1245 AM EDT...
            
The storms which prompted the warning have weakened, and no longer 
pose an immediate threat to life or property. Therefore the warning 
will be allowed to expire.  However gusty winds and heavy rain are 
still possible with these thunderstorms.

LAT...LON 4052 7625 4058 7605 4057 7602 4064 7598
      4068 7589 4049 7561 4027 7607 4036 7621
      4037 7623
TIME...MOT...LOC 0435Z 244DEG 27KT 4074 7566 4059 7568 4042 7576 4035
7591

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 11:49 PM EDTSpecial Weather StatementPHICarbon, Lehigh56 min
Aug 5, 12:10 AM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery51 min
Aug 5, 1:42 AM EDTSpecial Weather StatementPHIBucks, Montgomery, Northampton48 min
Aug 5, 1:59 AM EDTSpecial Weather StatementPHIChester, Montgomery46 min
Aug 5, 2:38 AM EDTSpecial Weather StatementPHIChester52 min
Aug 5, 2:41 AM EDTSpecial Weather StatementPHIBucks, Montgomery, Philadelphia49 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2017Every severe thunderstorm warning in 2017

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.