Alert archive / North Carolina / Mesoscale Discussions in 2011
Mesoscale Discussion 2136
The Storm Prediction Center issued this mesoscale discussion at Sep 5, 2011, 5:52 PM EDT for 19 counties in North Carolina; 18 counties in Virginia. It was in force for 53 min.
The area
The outline as issued.
The facts
- Issued
- Sep 5, 2011, 5:52 PM EDT (21:52 UTC)
- Expired
- Sep 5, 2011, 6:45 PM EDT
- In force
- 53 min
- Issued by
- the Storm Prediction Center
All 37 counties
Alamance County, NC, Alleghany County, NC, Ashe County, NC, Caswell County, NC, Chatham County, NC, Durham County, NC, Forsyth County, NC, Franklin County, NC, Granville County, NC, Guilford County, NC, Orange County, NC, Person County, NC, Rockingham County, NC, Stokes County, NC, Surry County, NC, Vance County, NC, Wake County, NC, Wilkes County, NC, Yadkin County, NC, Carroll County, VA, City of Danville, VA, City of Galax, VA, City of Martinsville, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, Floyd County, VA, Franklin County, VA, Grayson County, VA, Halifax County, VA, Henry County, VA, Montgomery County, VA, Patrick County, VA, Pittsylvania County, VA, Pulaski County, VA, Roanoke County, VA, Wythe County, VA
The radar
The Roanoke radar (KFCX), 95 km from the middle of the area, began a volume at 21:51 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
Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 9.9 hours before the alert went out and 45 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
- 109 J/kg
- Mixed-layer CIN
- -38 J/kg
- Mixed-layer LCL
- 689 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 62 m²/s²
- 0-3 km storm-relative helicity
- 48 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
521
ACUS11 KWNS 052152
SWOMCD
SPC MCD 052152
NCZ000-VAZ000-052245-
MESOSCALE DISCUSSION 2136
NWS STORM PREDICTION CENTER NORMAN OK
0452 PM CDT MON SEP 05 2011
AREAS AFFECTED...WRN NC/VA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 052152Z - 052245Z
A TORNADO THREAT APPEARS TO BE INCREASING ACROSS PORTIONS OF WRN NC
AND VA. A WW IS BEING CONSIDERED.
VAD WIND PROFILE DATA SHOWS INCREASINGLY FAVORABLE DEEP-LAYER SHEAR
IN ADVANCE OF THE REMNANTS OF T.D. LEE...WITH ABOUT 350 M2/S2 0-3 KM
SRH. A WEAK W-E BOUNDARY APPEARS TO BE ORIENTED ACROSS CNTRL
NC...FROM N OF CLT EWD TO GSB...LOCALLY INCREASING LOW LEVEL SRH
NEAR THE BOUNDARY. STRONGER MESOCYCLONES HAVE BEEN OBSERVED
RECENTLY...AND A LIMITED TEMPORAL THREAT OF TORNADOES MAY BE
POSSIBLE BEFORE THE ONSET OF DIURNAL COOLING AND ASSOCIATED
STABILIZATION OF THE BOUNDARY LAYER. AS SUCH...A WW MAY NEED TO BE
CONSIDERED.
..HURLBUT.. 09/05/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...AKQ...RAH...RNK...
LAT...LON 35837811 35617895 36058043 36218161 36798135 37328057
37387964 36707880 36167813 35837811SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 5, 3:42 PM EDT | Tornado Watch | SPC | Alexander, Burke, Cabarrus, Caldwell, Catawba, Cleveland and 11 more | 7 hr |
| Sep 5, 5:48 PM EDT | Mesoscale Discussion | SPC | Bladen, Brunswick, Columbus, Craven, Cumberland, Duplin and 19 more | 87 min |
| Sep 5, 6:12 PM EDT | Severe Thunderstorm Watch | SPC | Anson, Cumberland, Harnett, Hoke, Lee, Montgomery and 5 more | 4 hr |
| Sep 5, 6:29 PM EDT | Tornado Watch | SPC | Alamance, Alleghany, Caswell, Davidson, Forsyth, Guilford and 6 more | 10 hr |
| Sep 5, 7:37 PM EDT | Mesoscale Discussion | SPC | Alamance, Alexander, Burke, Cabarrus, Caldwell, Caswell and 24 more | 113 min |
Nearby
Mesoscale Discussions in North Carolina, 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.