Alert archive / West Virginia / Mesoscale Discussions in 2020

Mesoscale Discussion 819

June 4, 202011 counties in Ohio; 10 counties in Pennsylvania; 13 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Jun 4, 2020, 4:00 PM EDT for 11 counties in Ohio; 10 counties in Pennsylvania; 13 counties in West Virginia. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Jun 4, 2020, 4:00 PM EDT (20:00 UTC)
Expired: Jun 4, 2020, 5:30 PM EDT
In force: 90 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 249

All 34 counties

Athens County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Guernsey County, OH, Harrison County, OH, Jefferson County, OH, Monroe County, OH, Morgan County, OH, Noble County, OH, Washington County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Clarion County, PA, Greene County, PA, Lawrence County, PA, Mercer County, PA, Venango County, PA, Washington County, PA, Brooke County, WV, Doddridge County, WV, Hancock County, WV, Marion County, WV, Marshall County, WV, Monongalia County, WV, Ohio County, WV, Pleasants County, WV, Ritchie County, WV, Tyler County, WV, Wetzel County, WV, Wirt County, WV, Wood County, WV

The radar

The Pittsburgh radar (KPBZ), 41 km from the middle of the area, began a volume at 20:00 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, 8.0 hours before the alert went out and 46 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1364 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 100 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 4, 11:11 AM EDT	Mesoscale Discussion	SPC	Adams, Brown, Butler, Champaign, Clark, Clermont and 29 more	2 hr
Jun 4, 12:45 PM EDT	Mesoscale Discussion	SPC	Ashland, Athens, Belmont, Carroll, Columbiana, Coshocton and 29 more	90 min
Jun 4, 12:55 PM EDT	Severe Thunderstorm Watch	SPC	Ashland, Athens, Belmont, Carroll, Columbiana, Coshocton and 22 more	6 hr
Jun 4, 2:14 PM EDT	Mesoscale Discussion	SPC	Belmont, Carroll, Columbiana, Coshocton, Guernsey, Harrison and 6 more	61 min
Jun 4, 2:02 PM EDT	Mesoscale Discussion	SPC	Adams, Cumberland, Franklin, Fulton, Perry, York	118 min
Jun 4, 2:29 PM EDT	Severe Thunderstorm Watch	SPC	Adams, Bedford, Blair, Cambria, Cameron, Centre and 22 more	8 hr
Jun 4, 4:41 PM EDT	Mesoscale Discussion	SPC	Adams, Bedford, Blair, Cambria, Centre, Clinton and 16 more	94 min
Jun 4, 6:44 PM EDT	Mesoscale Discussion	SPC	Adams, Bedford, Berks, Blair, Centre, Chester and 19 more	91 min

Nearby

Mesoscale Discussions in West Virginia, 2020 Mesoscale Discussions in Ohio, 2020 Mesoscale Discussions in Pennsylvania, 2020 Every mesoscale discussion in 2020

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.