Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 96, NWS Philadelphia/Mount Holly

June 26, 2009Bucks County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 26, 2009, 6:01 PM EDT for Bucks County, Montgomery County, Pennsylvania. It was in force for 59 min. 3 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
Jun 26, 2009, 6:01 PM EDT (22:01 UTC)
Expired
Jun 26, 2009, 7:00 PM EDT
In force
59 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Bucks County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 96 km from the middle of the area, began a volume at 22:04 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
Jun 26, 6:16 PM EDTHAIL 19 S Geryville, PAQUARTER SIZE HAIL IN UPPER POTTSGROVE TWP.
Jun 26, 6:39 PM EDTHAIL 0.755 Ene Cedarville, PAPENNY SIZE HAIL IN SANATOGA.
Jun 26, 6:57 PM EDTHAIL 0.889 Sw Fricks, PANICKEL SIZE HAIL IN WORCESTER TWP.

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

The watch it was issued in

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

IssuedProductOfficeLasted
Jun 26, 2:42 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.0 hours before the alert went out and 111 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 2009-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1259 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, Phillips Aaf/Abe, MD at 12:00Z on 2009-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
1259 J/kg
Mixed-layer CIN
-73 J/kg
Mixed-layer LCL
969 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
26 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 262201
SVRPHI
PAC017-091-262300-
/O.NEW.KPHI.SV.W.0096.090626T2201Z-090626T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
601 PM EDT FRI JUN 26 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WEST CENTRAL BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 700 PM EDT

* AT 600 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 6 MILES
  WEST OF GILBERTSVILLE...OR 11 MILES EAST OF READING...AND MOVING
  EAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  GILBERTSVILLE AROUND 615 PM EDT...
  SPRING MOUNT AROUND 630 PM EDT...
  SOUDERTON AROUND 645 PM EDT...
  LANSDALE AROUND 650 PM EDT...
  FRICKS AROUND 655 PM EDT...
  CHALFONT AROUND 700 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT 
FRIDAY EVENING FOR EASTERN PENNSYLVANIA.

&&

LAT...LON 4042 7555 4041 7517 4011 7520 4027 7568
TIME...MOT...LOC 2200Z 280DEG 24KT 4035 7572

$$

SZATKOWSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 26, 3:31 PM EDTSevere Thunderstorm WarningPHIMonroe59 min
Jun 26, 3:53 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe82 min
Jun 26, 4:51 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe, Northampton69 min
Jun 26, 5:35 PM EDTSevere Thunderstorm WarningPHIBerks55 min
Jun 26, 6:16 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh59 min
Jun 26, 6:23 PM EDTSevere Thunderstorm WarningPHIChester, Montgomery52 min
Jun 26, 6:30 PM EDTSevere Thunderstorm WarningPHIBerks45 min
Jun 26, 6:41 PM EDTSevere Thunderstorm WarningPHIBucks41 min
Jun 26, 6:57 PM EDTSevere Thunderstorm WarningPHIMontgomery, Philadelphia48 min
Jun 26, 7:10 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia50 min
Jun 26, 7:15 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia60 min
Jun 26, 7:28 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia92 min
Jun 26, 7:30 PM EDTSevere Thunderstorm WarningPHIBerks45 min
Jun 26, 7:45 PM EDTSevere Thunderstorm WarningPHIPhiladelphia65 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2009Every severe thunderstorm warning in 2009

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.