Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 55, NWS Philadelphia/Mount Holly

June 11, 2007Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 11, 2007, 5:08 PM EDT for Delaware County, Pennsylvania. It was in force for 37 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 11, 2007, 5:08 PM EDT (21:08 UTC)
Expired
Jun 11, 2007, 5:45 PM EDT
In force
37 min
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

County Delaware County, PA

The radar

The Philadelphia radar (KDIX), 78 km from the middle of the area, began a volume at 21:09 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.1 hours before the alert went out and 87 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, Phillips Aaf/Abe, MD at 12:00Z on 2007-06-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 222 joules per kilogram.LCLLFCEL10008507005003002001001 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, Phillips Aaf/Abe, MD at 12:00Z on 2007-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 square meters per square second.1939Sfc1 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
222 J/kg
Mixed-layer CIN
-38 J/kg
Mixed-layer LCL
674 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
62 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 112109
SVRPHI
PAC045-112145-
/O.NEW.KPHI.SV.W.0055.070611T2108Z-070611T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
508 PM EDT MON JUN 11 2007

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF SPRINGFIELD...

* UNTIL 545 PM EDT

* AT 503 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A SEVERE THUNDERSTORM OVER NORTHEASTERN DELAWARE COUNTY. THIS
  STORM WAS LOCATED NEAR RADNOR TOWNSHIP...OR NEAR SPRINGFIELD...
  AND WAS MOVING SOUTH AT 10 TO 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  BROOMALL BY 515 PM EDT...
  DREXEL HILL AND EAST LANSDOWNE BY 520 PM EDT...
  SPRINGFIELD BY 525 PM EDT...
  SWARTHMORE...NETHER PROVIDENCE TOWNSHIP AND FOLCROFT BY 535 PM
  EDT...

LAT...LON 4002 7525 4003 7532 4005 7539 3986 7545
      3985 7528

$$

JRP

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 11, 3:39 AM EDTFlash Flood WarningPHIChester3 hr
Jun 11, 4:42 PM EDTSevere Thunderstorm WarningPHIMontgomery33 min

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.