Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 71, NWS Philadelphia/Mount Holly

July 19, 20134 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 19, 2013, 9:07 PM EDT for 4 counties in Pennsylvania. It was in force for 38 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 19, 2013, 9:07 PM EDT (01:07 UTC)
Expired
Jul 19, 2013, 9:45 PM EDT
In force
38 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

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

The radar

The Philadelphia radar (KDIX), 113 km from the middle of the area, began a volume at 01:08 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 19, 9:10 PM EDTTSTM WND DMGRockland Twp, PAA FEW TREES DOWN IN ROCKLAND TOWNSHIP.
Jul 19, 9:20 PM EDTHAIL 0.5Topton, PAHALF INCH HAIL REPORTED IN TOPTON. REPORT RELAYED BY EPAWA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 1.1 hours before the alert went out and 227 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 2013-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2483 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, Brookhaven, NY at 00:00Z on 2013-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
2483 J/kg
Mixed-layer CIN
-107 J/kg
Mixed-layer LCL
1143 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
78 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

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

096 
WUUS51 KPHI 200107
SVRPHI
PAC011-017-077-095-200145-
/O.NEW.KPHI.SV.W.0071.130720T0107Z-130720T0145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
907 PM EDT FRI JUL 19 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL BERKS COUNTY IN EASTERN PENNSYLVANIA...
  NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHERN LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  SOUTH CENTRAL NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...

* UNTIL 945 PM EDT

* AT 904 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM. THE STORM WAS NEAR LYONS...MOVING NORTHEAST AT
  35 MPH. THIS STORM IS CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH. 

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ANCIENT OAKS AND ZIONSVILLE AROUND 925 PM EDT...
  EMMAUS AROUND 930 PM EDT...
  ALLENTOWN AROUND 935 PM EDT...
  LEHIGH UNIVERSITY AND QUAKERTOWN AROUND 940 PM EDT...
  HELLERTOWN AND BETHLEHEM AROUND 945 PM EDT...

LAT...LON 4074 7539 4045 7521 4042 7549 4044 7553
      4041 7556 4038 7577 4049 7583
TIME...MOT...LOC 0107Z 245DEG 30KT 4045 7574

$$

ROBERTRSON
2 follow-up statements
704 
WWUS51 KPHI 200125
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
925 PM EDT FRI JUL 19 2013

PAC011-017-077-095-200145-
/O.CON.KPHI.SV.W.0071.000000T0000Z-130720T0145Z/
BERKS PA-BUCKS PA-LEHIGH PA-NORTHAMPTON PA-
925 PM EDT FRI JUL 19 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR SOUTH CENTRAL NORTHAMPTON...SOUTHEASTERN LEHIGH...NORTHWESTERN
BUCKS AND EAST CENTRAL BERKS COUNTIES...

AT 923 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED
NEAR MACUNGIE...OR 8 MILES SOUTHWEST OF ALLENTOWN...MOVING NORTHEAST
AT 45 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
EMMAUS AND ALLENTOWN AROUND 930 PM EDT...
COOPERSBURG AND FULLERTON AROUND 935 PM EDT...
HELLERTOWN AND LEHIGH UNIVERSITY AROUND 940 PM EDT...
FREEMANSBURG AND SPRINGTOWN AROUND 945 PM EDT...

LAT...LON 4074 7539 4045 7521 4042 7549 4044 7553
      4041 7556 4040 7561 4053 7567
TIME...MOT...LOC 0125Z 243DEG 38KT 4051 7554

$$

ROBERTSON
503 
WWUS51 KPHI 200140
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
940 PM EDT FRI JUL 19 2013

PAC011-017-077-095-200150-
/O.EXP.KPHI.SV.W.0071.000000T0000Z-130720T0145Z/
BERKS PA-BUCKS PA-LEHIGH PA-NORTHAMPTON PA-
940 PM EDT FRI JUL 19 2013

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL NORTHAMPTON...
SOUTHEASTERN LEHIGH...NORTHWESTERN BUCKS AND EAST CENTRAL BERKS
COUNTIES WILL EXPIRE AT 945 PM EDT...

THE STORM THAT PROMPTED THE WARNING HAS FALLEN BELOW SEVERE LEVELS. 

THE SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 4074 7539 4045 7521 4042 7549 4044 7553
      4041 7556 4040 7561 4053 7567
TIME...MOT...LOC 0140Z 243DEG 38KT 4058 7535

$$

ROBERTSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 8:24 PM EDTSpecial Weather StatementPHIBerks36 min
Jul 19, 8:33 PM EDTSevere Thunderstorm WarningPHIBerks42 min
Jul 19, 9:01 PM EDTSpecial Weather StatementPHIChester29 min
Jul 19, 9:41 PM EDTSpecial Weather StatementPHINorthampton34 min
Jul 20, 2:39 PM EDTSpecial Weather StatementPHIMonroe51 min
Jul 20, 3:31 PM EDTSpecial Weather StatementPHIMonroe59 min
Jul 20, 5:13 PM EDTSpecial Weather StatementPHILehigh62 min
Jul 20, 7:16 PM EDTSevere Thunderstorm WarningPHIBucks, Northampton59 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.