Alert archive / West Virginia / Mesoscale Discussions in 2011
Mesoscale Discussion 650
The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2011, 12:34 AM EDT for 9 counties in Virginia; 19 counties in West Virginia. It was in force for 26 min.
The area
The outline as issued.
The facts
- Issued
- Apr 28, 2011, 12:34 AM EDT (04:34 UTC)
- Expired
- Apr 28, 2011, 1:00 AM EDT
- In force
- 26 min
- Issued by
- the Storm Prediction Center
All 28 counties
Buchanan County, VA, City of Norton, VA, Dickenson County, VA, Lee County, VA, Russell County, VA, Scott County, VA, Tazewell County, VA, Washington County, VA, Wise County, VA, Barbour County, WV, Boone County, WV, Braxton County, WV, Clay County, WV, Fayette County, WV, Gilmer County, WV, Greenbrier County, WV, Harrison County, WV, Kanawha County, WV, Lewis County, WV, McDowell County, WV, Nicholas County, WV, Pocahontas County, WV, Raleigh County, WV, Randolph County, WV, Summers County, WV, Upshur County, WV, Webster County, WV, Wyoming County, WV
The radar
The Charleston,WV radar (KRLX), 60 km from the middle of the area, began a volume at 04:35 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 00:00Z, 4.6 hours before the alert went out and 171 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
- 372 J/kg
- Mixed-layer CIN
- -24 J/kg
- Mixed-layer LCL
- 1272 m above ground
- 0-6 km bulk shear
- 48 kt
- 0-1 km storm-relative helicity
- 226 m²/s²
- 0-3 km storm-relative helicity
- 335 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 3.0
The text
As transmitted, in the capitals the NWS used until 2016.
525
ACUS11 KWNS 280434
SWOMCD
SPC MCD 280434
WVZ000-VAZ000-KYZ000-280500-
MESOSCALE DISCUSSION 0650
NWS STORM PREDICTION CENTER NORMAN OK
1134 PM CDT WED APR 27 2011
AREAS AFFECTED...ERN KY...SERN OH...FAR SWRN VA AND SWRN-NRN WV
CONCERNING...TORNADO WATCH 239...
VALID 280434Z - 280500Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 239 CONTINUES.
ERN EXTENT OF WW 239 /ACROSS FAR SWRN VA AND SRN-ERN WV/ IS BEING
COORDINATED AT THIS TIME TO BE INCLUDED IN A NEW WATCH.
MEANWHILE...THE REST OF WW 239 WILL BE ALLOWED TO EXPIRE AS
SCHEDULED AT 05Z.
LATE EVENING SURFACE ANALYSIS SHOWED A COLD FRONT CONTINUING TO
ADVANCE EWD ACROSS KY AS THE ATTENDANT AREA OF LOW PRESSURE TRACKS
FROM CENTRAL INTO NERN IND. WSR-88D VWP SHOWED LOW LEVEL WINDS HAD
VEERED TO SWLY AT JKL. WRN EXTENT OF GREATER THETAE EXTENDED FROM
SWRN VA THROUGH SRN-ERN WV. THIS COMBINED WITH FAVORABLE DEEP LAYER
AND LOW LEVEL SHEAR WILL MAINTAIN A THREAT FOR EMBEDDED TORNADOES AS
65-75 KT SLY LLJ TRANSLATES ENEWD ACROSS THIS REGION TONIGHT.
..PETERS.. 04/28/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LWX...RNK...PBZ...RLX...MRX...JKL...
LAT...LON 37798196 38908106 39328047 39337983 38917948 38108007
37228138 36648168 36628326 37798196SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 27, 9:22 PM EDT | Mesoscale Discussion | SPC | Buchanan, Dickenson, Lee, Russell, Scott, Smyth and 5 more | 53 min |
| Apr 27, 10:12 PM EDT | Mesoscale Discussion | SPC | Albemarle, Alleghany, Amelia, Amherst, Appomattox, Arlington and 68 more | 63 min |
| Apr 28, 12:27 AM EDT | Mesoscale Discussion | SPC | Albemarle, Alleghany, Amherst, Appomattox, Arlington, Augusta and 65 more | 63 min |
| Apr 28, 12:41 AM EDT | Tornado Watch | SPC | Albemarle, Alleghany, Amelia, Amherst, Appomattox, Arlington and 78 more | 7 hr |
| Apr 28, 7:38 AM EDT | Tornado Watch | SPC | Accomack, Albemarle, Amelia, Amherst, Appomattox, Arlington and 83 more | 7 hr |
| Apr 28, 10:44 AM EDT | Mesoscale Discussion | SPC | Albemarle, Amelia, Amherst, Appomattox, Arlington, Bedford and 69 more | 61 min |
| Apr 28, 2:00 PM EDT | Mesoscale Discussion | SPC | Accomack, Amelia, Arlington, Brunswick, Caroline, Charles City and 47 more | 60 min |
| Apr 28, 2:41 PM EDT | Tornado Watch | SPC | Accomack, Charles City, Essex, Gloucester, Greensville, Isle of Wight and 30 more | 6 hr |
| Apr 28, 6:33 PM EDT | Mesoscale Discussion | SPC | Accomack, Charles City, Essex, Gloucester, Greensville, Henrico and 31 more | 57 min |
Nearby
Mesoscale Discussions in West Virginia, 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.