Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 41, NWS Philadelphia/Mount Holly

June 12, 2015Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 12, 2015, 6:53 PM EDT for Lehigh County, Northampton County, Pennsylvania. It was in force for 52 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 12, 2015, 6:53 PM EDT (22:53 UTC)
Expired
Jun 12, 2015, 7:45 PM EDT
In force
52 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 115 km from the middle of the area, began a volume at 22:55 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.9 hours before the alert went out and 213 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 12:00Z on 2015-06-12Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2015-06-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2083 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

003 
WUUS51 KPHI 122253
SVRPHI
PAC077-095-122345-
/O.NEW.KPHI.SV.W.0041.150612T2253Z-150612T2345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
653 PM EDT FRI JUN 12 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHWESTERN NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...

* UNTIL 745 PM EDT

* AT 653 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM
  WAS LOCATED NEAR ALLENTOWN...AND MOVING NORTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  ALLENTOWN...EASTON...BETHLEHEM...EMMAUS...NORTHAMPTON...WILSON...
  HELLERTOWN...NAZARETH...BATH...WEST EASTON...RIEGELSVILLE...
  STEUBEN...GLENDON...BEERSVILLE...ZIONSVILLE...CLAUSSVILLE...
  SCHNECKSVILLE...LEHIGH UNIVERSITY...NEFFS AND OLD ORCHARD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...DEADLY
LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER
COVERS THE ROAD.

&&

LAT...LON 4083 7539 4084 7536 4084 7535 4062 7520
      4060 7520 4058 7527 4054 7532 4044 7552
      4061 7577
TIME...MOT...LOC 2253Z 223DEG 41KT 4060 7553 

$$

JJM

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 11, 8:57 PM EDTSpecial Weather StatementPHISchuylkill48 min
Jun 11, 9:23 PM EDTSpecial Weather StatementPHILehigh, Northampton52 min
Jun 11, 9:33 PM EDTSpecial Weather StatementPHIBerks27 min
Jun 11, 9:41 PM EDTAreal Flood AdvisoryPHILehigh, Northampton4 hr
Jun 11, 9:54 PM EDTSpecial Weather StatementPHIBerks51 min
Jun 12, 4:38 PM EDTSpecial Weather StatementPHIMontgomery52 min
Jun 12, 4:57 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery48 min
Jun 12, 5:07 PM EDTSevere Thunderstorm WarningPHILehigh, Northampton38 min
Jun 12, 5:41 PM EDTSevere Thunderstorm WarningPHINorthampton49 min
Jun 12, 6:13 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton28 min
Jun 12, 7:27 PM EDTSevere Thunderstorm WarningPHINorthampton33 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015Every severe thunderstorm warning in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.