Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 34, NWS Philadelphia/Mount Holly

May 31, 2007Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 31, 2007, 9:33 PM EDT for Lehigh County, Pennsylvania. It was in force for 34 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
May 31, 2007, 9:33 PM EDT (01:33 UTC)
Expired
May 31, 2007, 10:07 PM EDT
In force
34 min
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

County Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 121 km from the middle of the area, began a volume at 01:33 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 00:00Z, 1.6 hours before the alert went out and 230 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 2007-06-01Temperature 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 2007-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 170 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
1386 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
170 m²/s²
0-3 km storm-relative helicity
218 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.

000 
WUUS51 KPHI 010135
SVRPHI
PAC077-010215-
/O.NEW.KPHI.SV.W.0034.070601T0133Z-070601T0215Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
933 PM EDT THU MAY 31 2007

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL AND SOUTHEASTERN LEHIGH COUNTY IN EASTERN PENNSYLVANIA...

* UNTIL 1015 PM EDT

* AT 928 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  AN AREA OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING PENNY SIZE
  HAIL...AND DAMAGING WINDS AROUND 60 MPH. THESE STORMS WERE LOCATED
  NEAR AND JUST NORTHWEST OF ANCIENT OAKS...OR ABOUT 8 MILES
  SOUTHWEST OF ALLENTOWN...AND MOVING SOUTHEAST AT 10 TO 15  MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  EMMAUS BY 940 PM EDT...

THUNDERSTORMS ARE CAPABLE OF PRODUCING HEAVY RAINFALL WHICH MAY
RESULT IN LOCALIZED AREAS OF FLOODING. DO NOT DRIVE IN AREAS WHERE
WATER IS CROSSING THE ROAD.

LAT...LON 4069 7561 4060 7573 4043 7549 4051 7540

$$

JRP
1 follow-up statement
000 
WWUS51 KPHI 010207
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1005 PM EDT THU MAY 31 2007

PAC077-010215-
/O.CAN.KPHI.SV.W.0034.000000T0000Z-070601T0215Z/
LEHIGH PA-
1005 PM EDT THU MAY 31 2007

...THE SEVERE THUNDERSTORM WARNING FOR LEHIGH COUNTY IS CANCELLED...

SEVERE THUNDERSTORMS HAVE WEAKENED AND ARE NO LONGER EXPECTED...SO 
THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.
 
HOWEVER...ADDITIONAL RAIN AND RUNOFF FROM PREVIOUS RAIN WILL 
CONTINUE TO CAUSE FLOODING AND A FLASH FLOOD WARNING HAS BEEN ISSUED 
FOR CENTRAL AND SOUTHERN LEHIGH COUNTY UNTIL 12:45 AM EARLY FRIDAY 
MORNING.

LAT...LON 4069 7561 4060 7573 4043 7549 4051 7540

$$

JRP

The office that day

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

IssuedProductOfficeCountiesLasted
May 31, 8:19 PM EDTFlash Flood WarningPHIBerks, Lehigh116 min
May 31, 8:30 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh45 min
May 31, 8:50 PM EDTSevere Thunderstorm WarningPHILehigh40 min
May 31, 9:50 PM EDTFlash Flood WarningPHILehigh3 hr
May 31, 11:27 PM EDTFlash Flood WarningPHILehigh93 min
Jun 1, 2:36 PM EDTSevere Thunderstorm WarningPHIMonroe54 min
Jun 1, 3:37 PM EDTSevere Thunderstorm WarningPHIMonroe38 min
Jun 1, 3:53 PM EDTSevere Thunderstorm WarningPHINorthampton82 min
Jun 1, 4:24 PM EDTSevere Thunderstorm WarningPHIMonroe66 min
Jun 1, 4:31 PM EDTFlash Flood WarningPHIMonroe3 hr
Jun 1, 5:33 PM EDTSevere Thunderstorm WarningPHIBerks87 min
Jun 1, 6:00 PM EDTFlash Flood WarningPHIBerks3 hr
Jun 1, 6:39 PM EDTSevere Thunderstorm WarningPHILehigh58 min
Jun 1, 6:50 PM EDTSevere Thunderstorm WarningPHIBerks62 min
Jun 1, 7:02 PM EDTSevere Thunderstorm WarningPHIBucks88 min
Jun 1, 7:03 PM EDTFlash Flood WarningPHILehigh3 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2007Every severe thunderstorm warning in 2007

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.