Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2006

Severe Thunderstorm Warning 109, NWS Philadelphia/Mount Holly

July 2, 2006Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 2, 2006, 6:09 PM EDT for Chester County, Pennsylvania. It was in force for 66 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
Jul 2, 2006, 6:09 PM EDT (22:09 UTC)
Expired
Jul 2, 2006, 7:15 PM EDT
In force
66 min
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

County Chester County, PA

The radar

The Philadelphia radar (KDIX), 106 km from the middle of the area, began a volume at 22:11 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 2, 4:03 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.2 hours before the alert went out and 200 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, Washington/Dulle, VA at 12:00Z on 2006-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 555 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, Washington/Dulle, VA at 12:00Z on 2006-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 171 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
555 J/kg
Mixed-layer CIN
-138 J/kg
Mixed-layer LCL
1325 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
171 m²/s²
0-3 km storm-relative helicity
143 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 022209
SVRPHI
PAC029-022315-
/O.NEW.KPHI.SV.W.0109.060702T2209Z-060702T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
609 PM EDT SUN JUL 2 2006

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA

* UNTIL 715 PM EDT

* AT 607 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR HONEY BROOK...OR ABOUT 13
  MILES SOUTH OF READING...AND MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ELVERSON BY 620 PM EDT...
  9 MILES NORTH OF DOWNINGTOWN BY 635 PM EDT...
  LIONVILLE BY 640 PM EDT...
  PHOENIXVILLE BY 650 PM EDT...

STORMS OF SIMILAR INTENSITY HAVE PRODUCED WIND DAMAGE ACROSS CENTRAL 
PENNSYLVANIA TODAY. THIS IS AN EXTREMELY DANGEROUS SITUATION. SEEK 
SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS
BE WARY FOR FREQUENT LIGHTNING.

LAT...LON 4017 7554 4014 7553 4015 7551 4014 7552
      4008 7551 3997 7552 4002 7586 4012 7593
      4020 7578 4022 7567

$$

TFG

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 2, 4:29 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe91 min
Jul 2, 5:47 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh58 min
Jul 2, 6:12 PM EDTSevere Thunderstorm WarningPHINorthampton63 min
Jul 2, 6:24 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery36 min
Jul 2, 6:54 PM EDTSevere Thunderstorm WarningPHIDelaware51 min
Jul 2, 6:58 PM EDTSevere Thunderstorm WarningPHIBucks32 min
Jul 2, 7:01 PM EDTSevere Thunderstorm WarningPHIMontgomery, Philadelphia59 min
Jul 2, 7:38 PM EDTSevere Thunderstorm WarningPHIBucks37 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2006Every severe thunderstorm warning in 2006

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.