Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 60, NWS Philadelphia/Mount Holly

July 27, 2018Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 27, 2018, 6:40 PM EDT for Berks County, Pennsylvania. It was in force for 50 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
Jul 27, 2018, 6:40 PM EDT (22:40 UTC)
Expired
Jul 27, 2018, 7:30 PM EDT
In force
50 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), 123 km from the middle of the area, began a volume at 22:40 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
Jul 27, 7:13 PM EDTTSTM WND DMG1 Se Robeson Twp, PADEBRIS IN ROADWAY CAUSED BY STRONG WINDS ON PLOW ROAD IN ROBESON TWP. TIME ESTIMATED FROM RADAR.
Jul 27, 7:13 PM EDTTSTM WND DMGWyomissing, PAPHOTOS SHOW A LARGE HARDWOOD TREE UPROOTED AND FALLEN ON A HOUSE. 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
Jul 27, 1:17 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.7 hours before the alert went out and 214 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 12:00Z on 2018-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 958 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 12:00Z on 2018-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
958 J/kg
Mixed-layer CIN
-54 J/kg
Mixed-layer LCL
1053 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
34 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

314 
WUUS51 KPHI 272240
SVRPHI
PAC011-272330-
/O.NEW.KPHI.SV.W.0060.180727T2240Z-180727T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
640 PM EDT FRI JUL 27 2018

The National Weather Service in Mount Holly NJ has issued a

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

* Until 730 PM EDT.

* At 639 PM EDT, severe thunderstorms were located along a line
  extending from Lyons to near Denver, moving east at 15 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Reading, Wyomissing, Birdsboro, Kutztown, Fleetwood, Sinking
  Spring, Laureldale, Wernersville, Topton, Bally, Bechtelsville,
  Lyons, New Morgan, Spring Ridge, Gilbertsville, Shillington, West
  Reading, Boyertown, Mount Penn and Mohnton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

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

&&

LAT...LON 4052 7578 4047 7556 4045 7553 4044 7553
      4025 7569 4014 7587 4032 7615
TIME...MOT...LOC 2239Z 267DEG 11KT 4046 7575 4026 7611 

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

CMS
2 follow-up statements
716 
WWUS51 KPHI 272311
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
711 PM EDT FRI JUL 27 2018

PAC011-272330-
/O.CON.KPHI.SV.W.0060.000000T0000Z-180727T2330Z/
Berks PA-
711 PM EDT FRI JUL 27 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM EDT
FOR SOUTHEASTERN BERKS COUNTY...

At 710 PM EDT, severe thunderstorms were located along a line
extending from near Topton to near New Morgan, moving east at 15 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Reading, Wyomissing, Birdsboro, Sinking Spring, Laureldale, Topton,
Bally, Bechtelsville, Lyons, New Morgan, Spring Ridge, Gilbertsville,
Shillington, West Reading, Boyertown, Mount Penn, Mohnton, Kenhorst,
St. Lawrence and West Lawn.

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 4030 7612 4041 7586 4051 7573 4047 7556
      4045 7553 4044 7553 4025 7569 4014 7587
TIME...MOT...LOC 2310Z 276DEG 13KT 4049 7564 4019 7593 

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

CMS
233 
WWUS51 KPHI 272329
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
729 PM EDT FRI JUL 27 2018

PAC011-272338-
/O.EXP.KPHI.SV.W.0060.000000T0000Z-180727T2330Z/
Berks PA-
729 PM EDT FRI JUL 27 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BERKS COUNTY WILL
EXPIRE AT 730 PM EDT...
    
The storms which prompted the warning are moving out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with these thunderstorms.

A severe thunderstorm watch remains in effect until 1000 PM EDT for
eastern and southeastern Pennsylvania.

LAT...LON 4030 7612 4041 7586 4051 7573 4047 7556
      4045 7553 4044 7553 4025 7569 4014 7587
TIME...MOT...LOC 2328Z 267DEG 11KT 4049 7557 4019 7586 

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 9:50 AM EDTFlash Flood WatchPHIBerks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more13 hr
Jul 27, 12:17 PM EDTAreal Flood AdvisoryPHICarbon, Monroe2 hr
Jul 27, 12:35 PM EDTFlash Flood WarningPHIMonroe63 min
Jul 27, 1:02 PM EDTAreal Flood AdvisoryPHIBerks3 hr
Jul 27, 1:08 PM EDTSpecial Weather StatementPHIBucks, Montgomery37 min
Jul 27, 1:19 PM EDTAreal Flood AdvisoryPHIBucks, Montgomery4 hr
Jul 27, 1:42 PM EDTSpecial Weather StatementPHIMontgomery48 min
Jul 27, 3:11 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh49 min
Jul 27, 3:47 PM EDTAreal Flood AdvisoryPHIBerks, Lehigh4 hr
Jul 27, 3:54 PM EDTFlash Flood WarningPHIBerks4 hr
Jul 27, 4:27 PM EDTSpecial Weather StatementPHIPhiladelphia33 min
Jul 27, 4:33 PM EDTSpecial Weather StatementPHICarbon, Monroe27 min
Jul 27, 4:43 PM EDTAreal Flood AdvisoryPHIBucks, Montgomery, Philadelphia5 hr
Jul 27, 4:44 PM EDTAreal Flood AdvisoryPHICarbon, Monroe7 hr
Jul 27, 5:00 PM EDTFlash Flood WarningPHIMonroe3 hr
Jul 27, 5:13 PM EDTSpecial Weather StatementPHIMonroe47 min
Jul 27, 5:27 PM EDTAreal Flood AdvisoryPHIBerks, Carbon, Lehigh, Northampton4 hr
Jul 27, 5:43 PM EDTSpecial Weather StatementPHILehigh47 min
Jul 27, 6:03 PM EDTSevere Thunderstorm WarningPHIChester42 min
Jul 27, 6:06 PM EDTAreal Flood AdvisoryPHIBerks, Chester3 hr
Jul 27, 6:36 PM EDTSpecial Weather StatementPHIBerks39 min
Jul 27, 7:03 PM EDTFlash Flood WarningPHIBerks3 hr
Jul 27, 7:09 PM EDTSevere Thunderstorm WarningPHIChester51 min
Jul 27, 7:37 PM EDTAreal Flood AdvisoryPHIBerks, Bucks, Chester, Delaware, Lehigh, Montgomery116 min
Jul 27, 7:46 PM EDTSpecial Weather StatementPHIMontgomery44 min
Jul 27, 7:49 PM EDTAreal Flood WarningPHIBerks4 hr
Jul 27, 7:49 PM EDTSpecial Weather StatementPHIBerks41 min
Jul 27, 7:53 PM EDTAreal Flood AdvisoryPHIBerks, Lehigh, Montgomery110 min
Jul 27, 7:55 PM EDTAreal Flood AdvisoryPHIBucks, Lehigh, Montgomery, Northampton108 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2018Every severe thunderstorm warning in 2018

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.