Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2005

Severe Thunderstorm Warning 90, NWS Philadelphia/Mount Holly

July 27, 2005Chester County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 27, 2005, 5:47 PM EDT for Chester County, Montgomery County, Pennsylvania. It was in force for 58 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: Jul 27, 2005, 5:47 PM EDT (21:47 UTC)
Expired: Jul 27, 2005, 6:45 PM EDT
In force: 58 min
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

Counties Chester County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 118 km from the middle of the area, began a volume at 21:48 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
Jul 27, 6:14 PM EDT	TSTM WND DMG	Royersford, PA	TREES AND WIRES DOWN.
Jul 27, 6:30 PM EDT	TSTM WND DMG	6 N Exton, PA	TREE DOWN BLOCKING ROUTE 82 IN WEST NANTMEAL TOWNSHIP.

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.

Issued	Product	Office	Lasted
Jul 27, 1:50 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.8 hours before the alert went out and 75 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: 1105 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 1506 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 29 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 272147
SVRPHI
PAC029-091-272245-
/O.NEW.KPHI.SV.W.0090.050727T2147Z-050727T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
547 PM EDT WED JUL 27 2005

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 645 PM EDT

* AT 544 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED 11 MILES WEST OF HONEY
  BROOK...OR ABOUT 10 MILES EAST OF LANCASTER...AND MOVING NORTHEAST
  AT 55 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HONEY BROOK AND COATESVILLE BY 555 PM EDT
  ELVERSON AND DOWNINGTOWN BY 600 PM EDT
  LIONVILLE AND WEST CHESTER BY 605 PM EDT
  PAOLI BY 610 PM EDT
  POTTSTOWN AND PHOENIXVILLE BY 615 PM EDT
  COLLEGEVILLE BY 620 PM EDT

LAT...LON 4009 7621 3983 7594 3989 7559 4023 7517
      4040 7549 4015 7586

HEAVY RAIN...WIND GUSTS TO 60 MPH AND HAIL ARE POSSIBLE WITH THESE 
STORMS.

$$

NIERENBERG

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 27, 4:06 PM EDT	Severe Thunderstorm Warning	PHI	Monroe	39 min
Jul 27, 4:12 PM EDT	Severe Thunderstorm Warning	PHI	Berks	48 min
Jul 27, 4:30 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Lehigh, Northampton	45 min
Jul 27, 5:17 PM EDT	Severe Thunderstorm Warning	PHI	Berks	43 min
Jul 27, 6:30 PM EDT	Severe Thunderstorm Warning	PHI	Philadelphia	45 min
Jul 27, 6:34 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	56 min
Jul 27, 6:40 PM EDT	Severe Thunderstorm Warning	PHI	Montgomery	35 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2005 Every severe thunderstorm warning in 2005

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.