Alert archive / Pennsylvania / Mesoscale Discussions in 2014

Mesoscale Discussion 293

April 4, 20147 counties in Ohio; 9 counties in Pennsylvania; 4 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Apr 4, 2014, 5:54 PM EDT for 7 counties in Ohio; 9 counties in Pennsylvania; 4 counties in West Virginia. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Apr 4, 2014, 5:54 PM EDT (21:54 UTC)
Expired: Apr 4, 2014, 7:30 PM EDT
In force: 96 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties Belmont County, OH, Columbiana County, OH, Harrison County, OH, Jefferson County, OH, Mahoning County, OH, Monroe County, OH, Noble County, OH, Allegheny County, PA, Beaver County, PA, Butler County, PA, Crawford County, PA, Greene County, PA, Lawrence County, PA, Mercer County, PA, Venango County, PA, Washington County, PA, Brooke County, WV, Hancock County, WV, Marshall County, WV, Ohio County, WV

The radar

The Pittsburgh radar (KPBZ), 38 km from the middle of the area, began a volume at 21:57 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 (KAGC), launched 12:00Z, 9.9 hours before the alert went out and 55 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 509 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 124 m²/s²
0-3 km storm-relative helicity: 112 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
Apr 4, 2:39 AM EDT	Mesoscale Discussion	SPC	Brown, Butler, Clermont, Clinton, Greene, Hamilton and 3 more	3 hr

Nearby

Mesoscale Discussions in Pennsylvania, 2014 Mesoscale Discussions in Ohio, 2014 Mesoscale Discussions in West Virginia, 2014 Every mesoscale discussion in 2014

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.