Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2006

Severe Thunderstorm Warning 257, NWS Philadelphia/Mount Holly

August 26, 2006Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 26, 2006, 4:11 AM EDT for Philadelphia County, Pennsylvania. It was in force for 49 min. 2 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: Aug 26, 2006, 4:11 AM EDT (08:11 UTC)
Expired: Aug 26, 2006, 5:00 AM EDT
In force: 49 min
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

County Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 58 km from the middle of the area, began a volume at 08:12 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

Time	Report	Where	Remark
Aug 26, 4:18 AM EDT	TSTM WND GST 47	3 Ne Philadelphia, PA	A PEAK THUNDERSTORM WIND GUST OF 47 MPH WAS MEASURED AT THE NORTHEAST PHILADELPHIA AIRPORT.
Aug 26, 4:20 AM EDT	TSTM WND DMG	3 Ne Philadelphia, PA	PHILADELPHIA POLICE REPORTED NUMEROUS TREES AND TREE LIMBS DOWN IN NORTHEAST PHILADELPHIA FROM ROOSEVELT BOULEVARD TO BYBERRY ROAD.

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 8.2 hours before the alert went out and 234 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 979 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 1772 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 104 m²/s²
0-3 km storm-relative helicity: 192 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 4.3

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 260812
SVRPHI
PAC101-260900-
/O.NEW.KPHI.SV.W.0257.060826T0811Z-060826T0900Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
411 AM EDT SAT AUG 26 2006

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA
  THIS INCLUDES THE CITY OF PHILADELPHIA

* UNTIL 500 AM EDT

* AT 410 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED NEAR NORTHEAST
  PHILADELPHIA...OR ABOUT 7 MILES NORTH OF PHILADELPHIA...AND MOVING
  SOUTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  PHILADELPHIA BY 415 AM EDT...
  7 MILES NORTHEAST OF CENTER CITY BY 420 AM EDT...

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.

LAT...LON 4011 7504 4005 7510 4006 7522 3996 7516
      4003 7503 4009 7497

$$

EBERWINE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 25, 10:43 PM EDT	Severe Thunderstorm Warning	PHI	Berks	32 min
Aug 25, 11:05 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Montgomery	40 min
Aug 25, 11:43 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Montgomery	47 min
Aug 25, 11:53 PM EDT	Severe Thunderstorm Warning	PHI	Delaware	52 min
Aug 26, 12:00 AM EDT	Severe Thunderstorm Warning	PHI	Philadelphia	45 min
Aug 26, 1:55 AM EDT	Severe Thunderstorm Warning	PHI	Bucks	50 min
Aug 26, 2:12 AM EDT	Severe Thunderstorm Warning	PHI	Carbon, Lehigh	48 min
Aug 26, 3:05 AM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh	55 min
Aug 26, 3:30 AM EDT	Severe Thunderstorm Warning	PHI	Montgomery	45 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2006 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.