Alert archive / West Virginia / Mesoscale Discussions in 2017
Mesoscale Discussion 1139
The Storm Prediction Center issued this mesoscale discussion at Jun 23, 2017, 4:53 PM EDT for 5 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 23, 2017, 4:53 PM EDT (20:53 UTC)
- Expired
- Jun 23, 2017, 7:00 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 51 counties
Bracken County, KY, Greenup County, KY, Harrison County, KY, Lewis County, KY, Mason County, KY, Pendleton County, KY, Robertson County, KY, Allegany County, MD, Garrett County, MD, Washington County, MD, Adams County, OH, Athens County, OH, Brown County, OH, Gallia County, OH, Jackson County, OH, Lawrence County, OH, Meigs County, OH, Pike County, OH, Scioto County, OH, Vinton County, OH, Washington County, OH, Adams County, PA, Bedford County, PA, Cumberland County, PA, Dauphin County, PA, Fayette County, PA, Franklin County, PA, Fulton County, PA, Greene County, PA, Huntingdon County, PA, Lancaster County, PA, Lebanon County, PA, Perry County, PA, Somerset County, PA, York County, PA, Doddridge County, WV, Harrison County, WV, Jackson County, WV, Marion County, WV, Mason County, WV, Mineral County, WV, Monongalia County, WV, Morgan County, WV, Pleasants County, WV, Preston County, WV, Ritchie County, WV, Taylor County, WV, Tyler County, WV, Wetzel County, WV, Wirt County, WV, Wood County, WV
The radar
The Pittsburgh radar (KPBZ), 134 km from the middle of the area, began a volume at 20:52 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, 8.9 hours before the alert went out and 124 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
- 36 J/kg
- Mixed-layer CIN
- -25 J/kg
- Mixed-layer LCL
- 520 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 263 m²/s²
- 0-3 km storm-relative helicity
- 188 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
328
ACUS11 KWNS 232054
SWOMCD
SPC MCD 232053
PAZ000-MDZ000-WVZ000-VAZ000-OHZ000-KYZ000-232300-
Mesoscale Discussion 1139
NWS Storm Prediction Center Norman OK
0353 PM CDT Fri Jun 23 2017
Areas affected...Northern KY...Southern OH...Northern WV...Western
MD...Southern PA
Concerning...Severe Thunderstorm Watch 366...
Valid 232053Z - 232300Z
The severe weather threat for Severe Thunderstorm Watch 366
continues.
SUMMARY...The threat for damaging winds and perhaps a brief tornado
continues.
DISCUSSION...Several clusters of thunderstorms are ongoing across
the valid portion of WW 366, with a tendency for convection to
evolve into short line segments. This mode is generally expected to
continue, given unidirectional southwesterly wind profiles across
the region. Periodic damaging wind gusts will be possible with these
line segments, while a brief tornado also cannot be ruled out, given
relatively strong 0-1 km shear of 20-30 kts noted in VWPs from CCX
and PBZ. A somewhat greater conditional threat of a tornado or two
would exist with any discrete cells that can be maintained, though
thus far convection has rather quickly evolved into line segments as
storms intensify.
A cluster of storms moving into southeast PA will begin to move out
of WW 366 within the hour, posing some severe threat into at least
southeast PA. Please refer to MCD 1135 for additional details
regarding the severe threat downstream of WW 366.
..Dean.. 06/23/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PHI...CTP...LWX...PBZ...RLX...JKL...ILN...LMK...
LAT...LON 38768446 39388245 39967991 40477789 40597644 40287580
39687638 39607762 39317904 38938129 38478294 38328439
38378442 38768446SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 23, 1:15 PM EDT | Mesoscale Discussion | SPC | Boone, Bracken, Campbell, Gallatin, Greenup, Kenton and 3 more | 2 hr |
| Jun 23, 1:39 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Anderson, Barren, Bath, Bell and 66 more | 2 hr |
| Jun 23, 2:20 PM EDT | Severe Thunderstorm Watch | SPC | Boyd, Bracken, Carter, Greenup, Lewis, Mason and 2 more | 8 hr |
| Jun 23, 3:32 PM EDT | Tornado Watch | SPC | Adair, Allen, Barren, Bath, Bell, Bourbon and 51 more | 6 hr |
| Jun 23, 5:50 PM EDT | Mesoscale Discussion | SPC | Adair, Bath, Bell, Bourbon, Boyd, Boyle and 54 more | 115 min |
| Jun 23, 3:35 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Carbon, Chester, Delaware, Lehigh and 6 more | 115 min |
| Jun 23, 5:09 PM EDT | Severe Thunderstorm Watch | SPC | Berks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more | 4 hr |
Nearby
Mesoscale Discussions in West Virginia, 2017Mesoscale Discussions in Pennsylvania, 2017Mesoscale Discussions in Ohio, 2017Every mesoscale discussion in 2017
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.