Alert archive / Pennsylvania / Mesoscale Discussions in 2019

Mesoscale Discussion 98

February 12, 20195 states

The Storm Prediction Center issued this mesoscale discussion at Feb 12, 2019, 4:16 AM EST for 5 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Feb 12, 2019, 4:16 AM EST (09:16 UTC)
Expired: Feb 12, 2019, 10:15 AM EST
In force: 6 hr
Issued by: the Storm Prediction Center

All 73 counties

Allegany County, MD, Baltimore County, MD, Carroll County, MD, Frederick County, MD, Garrett County, MD, Harford County, MD, Howard County, MD, Montgomery County, MD, Washington County, MD, Cattaraugus County, NY, Chautauqua County, NY, Adams County, PA, Armstrong County, PA, Bedford County, PA, Blair County, PA, Butler County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Crawford County, PA, Cumberland County, PA, Dauphin County, PA, Elk County, PA, Erie County, PA, Forest County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Lancaster County, PA, Lebanon County, PA, McKean County, PA, Mercer County, PA, Mifflin County, PA, Perry County, PA, Snyder County, PA, Somerset County, PA, Venango County, PA, Warren County, PA, York County, PA, Augusta County, VA, Bath County, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Frederick County, VA, Highland County, VA, Loudoun County, VA, Page County, VA, Rappahannock County, VA, Rockbridge County, VA, Rockingham 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, Pendleton County, WV, Pocahontas County, WV, Preston County, WV, Randolph County, WV, Tucker County, WV

The radar

The State College radar (KCCX), 115 km from the middle of the area, began a volume at 09:19 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

Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 9.3 hours before the alert went out and 316 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: 859 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 124 m²/s²
0-3 km storm-relative helicity: 287 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Feb 12, 10:48 AM EST	Mesoscale Discussion	SPC	Albany, Allegany, Bronx, Broome, Cattaraugus, Cayuga and 39 more	4 hr
Feb 12, 3:35 PM EST	Mesoscale Discussion	SPC	Albany, Allegany, Broome, Cayuga, Chemung, Chenango and 39 more	4 hr

Nearby

Mesoscale Discussions in Pennsylvania, 2019 Mesoscale Discussions in Virginia, 2019 Mesoscale Discussions in West Virginia, 2019 Every mesoscale discussion in 2019

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.