Alert archive / Virginia / Mesoscale Discussions in 2012
Mesoscale Discussion 186
The Storm Prediction Center issued this mesoscale discussion at Feb 29, 2012, 3:23 PM EST for 4 states. It was in force for 67 min.
The area
The outline as issued.
The facts
- Issued
- Feb 29, 2012, 3:23 PM EST (20:23 UTC)
- Expired
- Feb 29, 2012, 4:30 PM EST
- In force
- 67 min
- Issued by
- the Storm Prediction Center
All 37 counties
Alleghany County, NC, Ashe County, NC, Johnson County, TN, Alleghany County, VA, Bath County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Carroll County, VA, City of Bristol, VA, City of Buena Vista, VA, City of Covington, VA, City of Galax, VA, City of Lexington, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Floyd County, VA, Franklin County, VA, Giles County, VA, Grayson County, VA, Montgomery County, VA, Patrick County, VA, Pulaski County, VA, Roanoke County, VA, Rockbridge County, VA, Russell County, VA, Smyth County, VA, Tazewell County, VA, Washington County, VA, Wythe County, VA, Greenbrier County, WV, McDowell County, WV, Mercer County, WV, Monroe County, WV, Summers County, WV
The radar
The Roanoke radar (KFCX), 57 km from the middle of the area, began a volume at 20:26 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
Roanoke, VA (KRNK), launched 12:00Z, 8.4 hours before the alert went out and 122 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 651 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 313 m²/s²
- 0-3 km storm-relative helicity
- 338 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
979
ACUS11 KWNS 292023
SWOMCD
SPC MCD 292023
VAZ000-WVZ000-NCZ000-TNZ000-292130-
MESOSCALE DISCUSSION 0186
NWS STORM PREDICTION CENTER NORMAN OK
0223 PM CST WED FEB 29 2012
AREAS AFFECTED...WRN VA...NWRN NC...FAR NERN TN
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 292023Z - 292130Z
A TORNADO WATCH WILL LIKELY BE REQUIRED BY 22Z ACROSS WRN VA...NWRN
NC...FAR NERN TN.
LOW-LEVEL MOISTURE ADVECTION AND DESTABILIZATION WILL CONTINUE AHEAD
OF ONGOING SEVERE CONVECTION OVER KY/TN/WV...WITH THE SVR THREAT
SPREADING EWD DURING THE NEXT FEW HOURS. DESPITE MARGINAL
INSTABILITY...STRONG LOW/MID-LEVEL FLOW WILL PROMOTE A THREAT FOR
DMGG WIND GUSTS AND TORNADOES WITH BOWING LINE SEGMENTS...AND
LEWP/SUPERCELL STRUCTURES
..COHEN.. 02/29/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LWX...RNK...RLX...MRX...
LAT...LON 36938238 37678132 38338008 37907915 37057935 36488035
36318203 36938238SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 29, 5:36 PM EST | Mesoscale Discussion | SPC | Avery, Buncombe, Cherokee, Clay, Graham, Haywood and 10 more | 54 min |
| Feb 29, 6:37 PM EST | Tornado Watch | SPC | Avery, Buncombe, Cherokee, Clay, Graham, Haywood and 11 more | 3 hr |
| Feb 29, 1:49 AM EST | Mesoscale Discussion | SPC | Benton, Carroll, Chester, Crockett, Decatur, Dickson and 24 more | 56 min |
| Feb 29, 3:40 AM EST | Mesoscale Discussion | SPC | Cheatham, Clay, Davidson, Dickson, Hickman, Houston and 11 more | 65 min |
| Feb 29, 4:20 AM EST | Tornado Watch | SPC | Carroll, Crockett, Dyer, Gibson, Haywood, Henry and 6 more | 9 hr |
| Feb 29, 4:53 AM EST | Mesoscale Discussion | SPC | Carroll, Crockett, Dyer, Gibson, Haywood, Henry and 6 more | 97 min |
| Feb 29, 5:39 AM EST | Tornado Watch | SPC | Benton, Cheatham, Clay, Davidson, Dickson, Fentress and 14 more | 7 hr |
| Feb 29, 8:38 AM EST | Mesoscale Discussion | SPC | Benton, Cheatham, Clay, Davidson, DeKalb, Dickson and 15 more | 67 min |
| Feb 29, 9:07 AM EST | Mesoscale Discussion | SPC | Carroll, Crockett, Dyer, Gibson, Haywood, Henry and 6 more | 53 min |
| Feb 29, 12:11 PM EST | Mesoscale Discussion | SPC | Anderson, Benton, Campbell, Cannon, Carroll, Cheatham and 49 more | 2 hr |
| Feb 29, 12:31 PM EST | Tornado Watch | SPC | Anderson, Bedford, Benton, Bledsoe, Campbell, Cannon and 68 more | 8 hr |
| Feb 29, 12:46 PM EST | Mesoscale Discussion | SPC | Fayette, Hardeman, Hardin, McNairy | 89 min |
| Feb 29, 2:48 PM EST | Tornado Watch | SPC | Franklin, Lincoln, Moore | 7 hr |
| Feb 29, 4:34 PM EST | Mesoscale Discussion | SPC | Anderson, Bedford, Benton, Campbell, Cannon, Carroll and 52 more | 116 min |
| Feb 29, 1:37 PM EST | Tornado Watch | SPC | Buchanan, Dickenson | 7 hr |
| Feb 29, 3:43 PM EST | Tornado Watch | SPC | Alleghany, Bath, Bedford, Bland, Botetourt, Carroll and 22 more | 5 hr |
| Feb 29, 1:24 PM EST | Mesoscale Discussion | SPC | Boone, Cabell, Calhoun, Jackson, Kanawha, Lincoln and 10 more | 36 min |
| Feb 29, 4:18 PM EST | Mesoscale Discussion | SPC | Barbour, Boone, Braxton, Brooke, Cabell, Calhoun and 31 more | 87 min |
Nearby
Mesoscale Discussions in Virginia, 2012Mesoscale Discussions in West Virginia, 2012Mesoscale Discussions in North Carolina, 2012Every mesoscale discussion in 2012
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.