Alert archive / West Virginia / Mesoscale Discussions in 2021
Mesoscale Discussion 944
The Storm Prediction Center issued this mesoscale discussion at Jun 13, 2021, 12:13 PM EDT for 5 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 13, 2021, 12:13 PM EDT (16:13 UTC)
- Expired
- Jun 13, 2021, 2:15 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 60%
All 57 counties
Allegany County, MD, Garrett County, MD, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Guernsey County, OH, Harrison County, OH, Jefferson County, OH, Mahoning County, OH, Monroe County, OH, Noble County, OH, Tuscarawas County, OH, Washington County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Bedford County, PA, Butler County, PA, Cambria County, PA, Clarion County, PA, Fayette County, PA, Greene County, PA, Indiana County, PA, Lawrence County, PA, Somerset County, PA, Washington County, PA, Westmoreland County, PA, City of Winchester, VA, Frederick County, VA, Rockingham County, VA, Shenandoah County, VA, Barbour County, WV, Brooke County, WV, Doddridge County, WV, Gilmer County, WV, Grant County, WV, Hampshire County, WV, Hancock County, WV, Hardy County, WV, Harrison County, WV, Lewis County, WV, Marion County, WV, Marshall County, WV, Mineral County, WV, Monongalia County, WV, Morgan County, WV, Ohio County, WV, Pendleton County, WV, Pleasants County, WV, Preston County, WV, Randolph County, WV, Ritchie County, WV, Taylor County, WV, Tucker County, WV, Tyler County, WV, Upshur County, WV, Wetzel County, WV
The radar
The Pittsburgh radar (KPBZ), 92 km from the middle of the area, began a volume at 16:14 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.
The nearest sounding before it
Pittsburgh, PA (KPIT), launched 12:00Z, 4.2 hours before the alert went out and 76 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.
- Mixed-layer CAPE
- 1001 J/kg
- Mixed-layer CIN
- -33 J/kg
- Mixed-layer LCL
- 944 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 53 m²/s²
- 0-3 km storm-relative helicity
- 47 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.3
The text
As transmitted.
048
ACUS11 KWNS 131614
SWOMCD
SPC MCD 131613
MDZ000-WVZ000-PAZ000-VAZ000-OHZ000-131815-
Mesoscale Discussion 0944
NWS Storm Prediction Center Norman OK
1113 AM CDT Sun Jun 13 2021
Areas affected...portions of far southeast Ohio...southwest
Pennsylvania into northern West Virginia and northwest Virginia
Concerning...Severe potential...Watch possible
Valid 131613Z - 131815Z
Probability of Watch Issuance...60 percent
SUMMARY...The severe potential is increasing across portions of the
Mid Atlantic. Damaging winds are the primary threat. A Severe
Thunderstorm Watch may be needed if storms continue to intensify and
increase in coverage.
DISCUSSION...Multicellular clusters have recently experienced an
uptick along the southwest flank of an ongoing MCS, on the leading
edge of the cold pool. The MCS is propagating southward towards 80+
F surface temperatures, with upper 60s to 70 F dewpoints
contributing to 1000+ J/kg MLCAPE. Though only 25 kts of effective
bulk shear are in place, and mid-level lapse rates are generally
under 6 C/km, continued surface heating with the rich moisture in
place is expected to support robust storm development into early
afternoon, both ahead of the MCS cold pool and along the cold front.
Wet downbursts and merging cold pools may support at least a few
damaging gusts with the stronger (albeit shorter lived)
multicellular clusters. Damaging gust potential may be high enough
to warrant the issuance of a Severe Thunderstorm Watch over the next
couple of hours.
..Squitieri/Grams.. 06/13/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CTP...LWX...PBZ...RLX...CLE...
LAT...LON 40308170 40698125 41088070 41338000 41237933 40707854
39887830 39267812 38887827 38557856 38397910 38377963
38588043 38928110 39418176 40308170SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 13, 12:32 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Calvert, Carroll, Charles, Frederick, Howard and 3 more | 118 min |
| Jun 13, 3:26 PM EDT | Mesoscale Discussion | SPC | Garrett | 94 min |
| Jun 13, 12:50 PM EDT | Severe Thunderstorm Watch | SPC | Adams, Athens, Belmont, Carroll, Columbiana, Coshocton and 30 more | 7 hr |
| Jun 13, 2:04 PM EDT | Mesoscale Discussion | SPC | Clermont, Hamilton | 56 min |
| Jun 13, 4:31 PM EDT | Mesoscale Discussion | SPC | Adams, Gallia, Jackson, Lawrence, Scioto | 89 min |
| Jun 13, 2:38 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Centre, Clearfield and 20 more | 2 hr |
| Jun 13, 3:26 PM EDT | Severe Thunderstorm Watch | SPC | Blair, Bradford, Cambria, Cameron, Centre, Clearfield and 20 more | 7 hr |
| Jun 13, 4:56 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Centre, Clarion and 25 more | 94 min |
| Jun 13, 7:21 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Carbon, Centre and 20 more | 84 min |
| Jun 13, 4:56 PM EDT | Severe Thunderstorm Watch | SPC | Alleghany, Bath, Bland, Botetourt, Buchanan, Craig and 7 more | 5 hr |
| Jun 13, 7:05 PM EDT | Mesoscale Discussion | SPC | Alleghany, Bath, Botetourt, Craig, Giles, Roanoke and 3 more | 85 min |
Nearby
Mesoscale Discussions in West Virginia, 2021Mesoscale Discussions in Pennsylvania, 2021Mesoscale Discussions in Ohio, 2021Every mesoscale discussion in 2021
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.