Alert archive / West Virginia / Mesoscale Discussions in 2007

Mesoscale Discussion 1138

June 13, 20074 states

The Storm Prediction Center issued this mesoscale discussion at Jun 13, 2007, 7:30 PM EDT for 4 states. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Jun 13, 2007, 7:30 PM EDT (23:30 UTC)
Expired: Jun 13, 2007, 9:00 PM EDT
In force: 90 min
Issued by: the Storm Prediction Center

All 53 counties

Allegany County, MD, Charles County, MD, Garrett County, MD, Montgomery County, MD, Fayette County, PA, Greene County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Harrisonburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Frederick County, VA, Highland County, VA, Loudoun County, VA, Madison County, VA, Page County, VA, Prince William County, VA, Rappahannock County, VA, Rockingham County, VA, Shenandoah County, VA, Stafford County, VA, Warren County, VA, Barbour County, WV, Berkeley County, WV, Braxton County, WV, Doddridge County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Harrison County, WV, Jefferson County, WV, Lewis County, WV, Marion County, WV, Marshall County, WV, Mineral County, WV, Monongalia County, WV, Morgan County, WV, Pendleton County, WV, Pocahontas County, WV, Preston County, WV, Randolph County, WV, Taylor County, WV, Tucker County, WV, Upshur County, WV, Webster County, WV, Wetzel County, WV

The radar

The Sterling radar (KLWX), 161 km from the middle of the area, began a volume at 23:31 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, 11.5 hours before the alert went out and 149 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: 339 J/kg
Mixed-layer CIN: -157 J/kg
Mixed-layer LCL: 1257 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 71 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
Jun 13, 11:54 AM EDT	Mesoscale Discussion	SPC	Allegany, Garrett, Washington	66 min
Jun 13, 1:24 PM EDT	Severe Thunderstorm Watch	SPC	Allegany, Anne Arundel, Baltimore, Calvert, Carroll, Charles and 9 more	8 hr
Jun 13, 3:13 PM EDT	Mesoscale Discussion	SPC	Allegany, Anne Arundel, Baltimore, Calvert, Carroll, Cecil and 14 more	92 min
Jun 13, 5:59 PM EDT	Mesoscale Discussion	SPC	Buchanan, Dickenson	61 min
Jun 13, 6:31 PM EDT	Severe Thunderstorm Watch	SPC	Cabell, Jackson, Mason, Pleasants, Putnam, Ritchie and 2 more	4 hr

Nearby

Mesoscale Discussions in West Virginia, 2007 Mesoscale Discussions in Virginia, 2007 Mesoscale Discussions in Maryland, 2007 Every mesoscale discussion in 2007

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.