Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 121, NWS Philadelphia/Mount Holly

November 18, 20136 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Nov 18, 2013, 1:58 AM EST for 6 counties in Pennsylvania. It was in force for 62 min. 3 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
Nov 18, 2013, 1:58 AM EST (06:58 UTC)
Expired
Nov 18, 2013, 3:00 AM EST
In force
62 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Berks County, PA, Bucks County, PA, Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 145 km from the middle of the area, began a volume at 06:58 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
Nov 18, 2:39 AM ESTTSTM WND GST 52Mount Pocono Airport, PA
Nov 18, 3:10 AM ESTTSTM WND DMGLehighton, PAPOWER LINES REPORTED DOWN WITH POWER OUTAGES ALSO REPORTED IN LEHIGHTON.
Nov 18, 3:10 AM ESTTSTM WND DMGLehighton, PASCATTER POWER OUTAGES.

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
Nov 18, 1:07 AM ESTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 7.0 hours before the alert went out and 238 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, Brookhaven, NY at 00:00Z on 2013-11-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Brookhaven, NY at 00:00Z on 2013-11-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 135 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
520 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
135 m²/s²
0-3 km storm-relative helicity
126 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

282 
WUUS51 KPHI 180658
SVRPHI
PAC011-017-025-077-089-095-180800-
/O.NEW.KPHI.SV.W.0121.131118T0658Z-131118T0800Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
158 AM EST MON NOV 18 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  MONROE COUNTY IN NORTHEAST PENNSYLVANIA...
  CARBON COUNTY IN NORTHEAST PENNSYLVANIA...
  NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...

* UNTIL 300 AM EST

* AT 153 AM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS. THESE SEVERE STORMS EXTENDED FROM
  CONYNGHAM TO MINERSVILLE TO FREDERICKSBURG...MOVING EAST AT 70 MPH.
  THESE STORMS ARE CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF
  60 MPH. 

* SEVERE THUNDERSTORMS WILL BE NEAR...
  WEATHERLY AND BERNVILLE AROUND 205 AM EST...
  NESQUEHONING AND LEESPORT AROUND 210 AM EST...
  LAKE HARMONY AND BLAKESLEE AROUND 215 AM EST...
  POCONO RACEWAY AND LONG POND AROUND 220 AM EST...
  TANNERSVILLE AND SCOTRUN AROUND 225 AM EST...
  ANALOMINK AND HERNYVILLE AROUND 230 AM EST...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS LINE OF SEVERE THUNDERSTORMS HAS A HISTORY OF PRODUCING WIND 
DAMAGE IN CENTRAL AND PORTIONS OF EASTERN PENNSYLVANIA. DO NOT STAY 
OUTDOORS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 500 AM EST MONDAY
MORNING FOR NORTHWEST NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4058 7603 4065 7599 4074 7577 4092 7600
      4100 7575 4110 7576 4114 7569 4113 7564
      4123 7554 4125 7512 4116 7515 4115 7510
      4042 7530 4042 7549 4044 7552 4042 7555
      4043 7634 4049 7644
TIME...MOT...LOC 0657Z 269DEG 61KT 4103 7598 4073 7618
          4047 7630

$$

FORECASTER: HEAVENER

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 18, 2:28 AM ESTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Delaware, Montgomery62 min
Nov 18, 2:54 AM ESTSevere Thunderstorm WarningPHIBucks, Lehigh, Monroe, Northampton66 min
Nov 18, 3:29 AM ESTSevere Thunderstorm WarningPHIBucks, Delaware, Montgomery, Philadelphia61 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2013Every severe thunderstorm warning in 2013

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.