Alert archive / Pennsylvania / Mesoscale Discussions in 2005

Mesoscale Discussion 1740

July 13, 20054 states

The Storm Prediction Center issued this mesoscale discussion at Jul 13, 2005, 2:27 PM EDT for 4 states. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Jul 13, 2005, 2:27 PM EDT (18:27 UTC)
Expired: Jul 13, 2005, 4:00 PM EDT
In force: 93 min
Issued by: the Storm Prediction Center

All 37 counties

Allegany County, MD, Garrett County, MD, Armstrong County, PA, Bedford County, PA, Blair County, PA, Butler County, PA, Cambria County, PA, Clarion County, PA, Crawford County, PA, Fayette County, PA, Forest County, PA, Fulton County, PA, Indiana County, PA, Jefferson County, PA, Somerset County, PA, Venango County, PA, Warren County, PA, Westmoreland County, PA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fauquier County, VA, Frederick County, VA, Greene County, VA, Madison County, VA, Orange County, VA, Page County, VA, Rappahannock County, VA, Shenandoah County, VA, Warren County, VA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Mineral County, WV, Morgan County, WV

The radar

The Sterling radar (KLWX), 142 km from the middle of the area, began a volume at 18:31 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

Pittsburgh, PA (KPIT), launched 12:00Z, 6.5 hours before the alert went out and 133 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: 441 J/kg
Mixed-layer CIN: -83 J/kg
Mixed-layer LCL: 1206 m above ground
0-6 km bulk shear: 4 kt
0-1 km storm-relative helicity: -18 m²/s²
0-3 km storm-relative helicity: 12 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.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 13, 5:18 PM EDT	Mesoscale Discussion	SPC	Berks, Blair, Centre, Cumberland, Dauphin, Franklin and 11 more	3 hr

Nearby

Mesoscale Discussions in Pennsylvania, 2005 Mesoscale Discussions in Virginia, 2005 Mesoscale Discussions in West Virginia, 2005 Every mesoscale discussion 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.