Alert archive / Ohio / Mesoscale Discussions in 2015

Mesoscale Discussion 989

June 12, 201515 counties in Ohio; 13 counties in Pennsylvania; 8 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Jun 12, 2015, 4:21 PM EDT for 15 counties in Ohio; 13 counties in Pennsylvania; 8 counties in West Virginia. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Jun 12, 2015, 4:21 PM EDT (20:21 UTC)
Expired: Jun 12, 2015, 5:45 PM EDT
In force: 84 min
Issued by: the Storm Prediction Center

All 36 counties

Athens County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Guernsey County, OH, Harrison County, OH, Hocking County, OH, Jefferson County, OH, Monroe County, OH, Morgan County, OH, Noble County, OH, Pike County, OH, Ross County, OH, Vinton County, OH, Washington County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Greene County, PA, Indiana County, PA, Jefferson County, PA, Lawrence County, PA, Washington County, PA, Westmoreland County, PA, Brooke County, WV, Hancock County, WV, Marshall County, WV, Ohio County, WV, Pleasants County, WV, Tyler County, WV, Wetzel County, WV, Wood County, WV

The radar

The Pittsburgh radar (KPBZ), 101 km from the middle of the area, began a volume at 20:22 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 296Jun 12, 7:20 PM EDT

The nearest sounding before it

Pittsburgh, PA (KAGC), launched 12:00Z, 8.4 hours before the alert went out and 106 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: 32 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 1545 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 72 m²/s²
0-3 km storm-relative helicity: 142 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 12, 12:52 PM EDT	Mesoscale Discussion	SPC	Allen, Ashland, Ashtabula, Auglaize, Carroll, Champaign and 40 more	113 min
Jun 12, 1:14 PM EDT	Severe Thunderstorm Watch	SPC	Ashland, Ashtabula, Auglaize, Belmont, Butler, Carroll and 59 more	8 hr
Jun 12, 4:32 PM EDT	Severe Thunderstorm Watch	SPC	Allen, Paulding, Putnam, Van Wert	4 hr
Jun 12, 6:53 PM EDT	Mesoscale Discussion	SPC	Allen, Ashland, Athens, Auglaize, Belmont, Butler and 47 more	97 min
Jun 12, 2:03 PM EDT	Mesoscale Discussion	SPC	Adams, Carbon, Columbia, Cumberland, Dauphin, Franklin and 14 more	87 min
Jun 12, 2:54 PM EDT	Severe Thunderstorm Watch	SPC	McKean, Potter, Tioga, Warren	6 hr
Jun 12, 7:25 PM EDT	Severe Thunderstorm Watch	SPC	Bedford, Blair, Bradford, Cambria, Centre, Columbia and 17 more	4 hr

Nearby

Mesoscale Discussions in Ohio, 2015 Mesoscale Discussions in Pennsylvania, 2015 Mesoscale Discussions in West Virginia, 2015 Every mesoscale discussion in 2015

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.