Alert archive / West Virginia / Mesoscale Discussions in 2011
Mesoscale Discussion 412
The Storm Prediction Center issued this mesoscale discussion at Apr 11, 2011, 12:24 PM EDT for 6 states. It was in force for 36 min.
The area
The outline as issued.
The facts
- Issued
- Apr 11, 2011, 12:24 PM EDT (16:24 UTC)
- Expired
- Apr 11, 2011, 1:00 PM EDT
- In force
- 36 min
- Issued by
- the Storm Prediction Center
All 84 counties
Boyd County, KY, Breathitt County, KY, Carter County, KY, Clay County, KY, Elliott County, KY, Estill County, KY, Floyd County, KY, Greenup County, KY, Jackson County, KY, Johnson County, KY, Knott County, KY, Lawrence County, KY, Lee County, KY, Leslie County, KY, Letcher County, KY, Magoffin County, KY, Martin County, KY, Menifee County, KY, Morgan County, KY, Owsley County, KY, Perry County, KY, Pike County, KY, Powell County, KY, Rowan County, KY, Wolfe County, KY, Garrett County, MD, Gallia County, OH, Lawrence County, OH, Meigs County, OH, Monroe County, OH, Washington County, OH, Fayette County, PA, Greene County, PA, Somerset County, PA, Buchanan County, VA, City of Norton, VA, Dickenson County, VA, Russell County, VA, Tazewell County, VA, Wise County, VA, Barbour County, WV, Boone County, WV, Braxton County, WV, Cabell County, WV, Calhoun County, WV, Clay County, WV, Doddridge County, WV, Fayette County, WV, Gilmer County, WV, Grant County, WV, Greenbrier County, WV, Harrison County, WV, Jackson County, WV, Kanawha County, WV, Lewis County, WV, Lincoln County, WV, Logan County, WV, Marion County, WV, Marshall County, WV, Mason County, WV, McDowell County, WV, Mercer County, WV, Mingo County, WV, Monongalia County, WV, Nicholas County, WV, Pleasants County, WV, Pocahontas County, WV, Preston County, WV, Putnam County, WV, Raleigh County, WV, Randolph County, WV, Ritchie County, WV, Roane County, WV, Summers County, WV, Taylor County, WV, Tucker County, WV, Tyler County, WV, Upshur County, WV, Wayne County, WV, Webster County, WV, Wetzel County, WV, Wirt County, WV, Wood County, WV, Wyoming County, WV
The radar
The Charleston,WV radar (KRLX), 15 km from the middle of the area, began a volume at 16:27 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
Cncnati-Daytn, OH (KILN), launched 12:00Z, 4.4 hours before the alert went out and 219 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
- 513 J/kg
- Mixed-layer CIN
- -65 J/kg
- Mixed-layer LCL
- 893 m above ground
- 0-6 km bulk shear
- 61 kt
- 0-1 km storm-relative helicity
- 318 m²/s²
- 0-3 km storm-relative helicity
- 339 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 8.4
The text
As transmitted, in the capitals the NWS used until 2016.
355
ACUS11 KWNS 111624
SWOMCD
SPC MCD 111624
MDZ000-PAZ000-WVZ000-VAZ000-OHZ000-KYZ000-111700-
MESOSCALE DISCUSSION 0412
NWS STORM PREDICTION CENTER NORMAN OK
1124 AM CDT MON APR 11 2011
AREAS AFFECTED...ERN KY...WV...AND PARTS OF SWRN PA
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 111624Z - 111700Z
A NEW TORNADO WATCH WILL BE NEEDED SOON FROM ERN KY...THROUGH MUCH
OF WV AND POSSIBLY INTO SWRN PA. DAMAGING WINDS SHOULD BE THE
PRIMARY THREAT...BUT LOW LEVEL SHEAR /EFFECTIVE SRH 100-200 M2 PER
S2/ IS SUFFICIENT FOR A TORNADO THREAT.
THE AIR MASS...ALTHOUGH ONLY MARGINALLY UNSTABLE AT THIS
TIME...ACROSS ERN KY...WV INTO SWRN PA WILL CONTINUE TO DESTABILIZE
GIVEN ADDITIONAL SURFACE HEATING COMBINED WITH SURFACE DEWPOINTS
AROUND 60 F. EFFECTIVE BULK SHEAR IS ALREADY SUPPORTIVE FOR
ORGANIZED STORMS WITH VALUES OF 40-60 KT. MEANWHILE... A FAST
MOVING /ENE AT 55 KT/ LINE OF CONVECTION OVER SRN KY IS ATTENDANT TO
A LONG-LIVED MCV...WITH THIS ACTIVITY LOCATED ALONG A WIND SHIFT
EXTENDING FROM SWRN TN TO FAR WRN WV AND FAR NWRN PA. GIVEN THE
FORWARD SPEED OF THE SRN KY CONVECTION AND FORCING FOR ASCENT AS
GREATER HEIGHT FALLS SPREAD EWD AHEAD OF THE TROUGH EXTENDING FROM
THE UPPER GREAT LAKES TO SRN PLAINS...TSTMS ARE EXPECTED TO DEVELOP
AND SPREAD ENEWD ACROSS ERN KY INTO WV AND MAY AFFECT SWRN PA.
HOWEVER... ONGOING CONVECTION OVER SWRN PA MAY TEND TO LIMIT
AFTERNOON DESTABILIZATION AND THE OVERALL NWD EXTENT OF SEVERE
WEATHER INTO THIS REGION.
..PETERS.. 04/11/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...MRX...JKL...ILN...
LAT...LON 37358431 38578308 39388187 40058090 40057887 38907921
37738031 37058148 36848211 37018363 37358431SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 11, 9:58 AM EDT | Mesoscale Discussion | SPC | Adair, Allen, Anderson, Barren, Bourbon, Boyle and 37 more | 62 min |
| Apr 11, 11:31 AM EDT | Tornado Watch | SPC | Adair, Allen, Anderson, Barren, Bourbon, Boyle and 26 more | 6 hr |
| Apr 11, 11:41 AM EDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Casey, Clinton, Cumberland and 8 more | 64 min |
| Apr 11, 12:47 PM EDT | Tornado Watch | SPC | Bath, Bell, Boyd, Breathitt, Carter, Clay and 31 more | 6 hr |
| Apr 11, 1:37 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Anderson, Barren, Bourbon, Boyle and 31 more | 53 min |
| Apr 11, 3:44 PM EDT | Mesoscale Discussion | SPC | Bath, Bell, Boyd, Breathitt, Carter, Clay and 31 more | 61 min |
| Apr 11, 6:11 PM EDT | Tornado Watch | SPC | Adair, Bell, Breathitt, Casey, Clay, Clinton and 18 more | 7 hr |
| Apr 11, 6:43 PM EDT | Mesoscale Discussion | SPC | Carroll | 62 min |
| Apr 11, 1:48 AM EDT | Mesoscale Discussion | SPC | Defiance, Williams | 87 min |
Nearby
Mesoscale Discussions in West Virginia, 2011Mesoscale Discussions in Kentucky, 2011Mesoscale Discussions in Virginia, 2011Every mesoscale discussion in 2011
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.