Alert archive / Virginia / Mesoscale Discussions in 2003
Mesoscale Discussion 921
The Storm Prediction Center issued this mesoscale discussion at May 10, 2003, 4:46 PM EDT for 17 counties in North Carolina; 22 counties in Virginia. It was in force for 89 min.
The area
The outline as issued.
The facts
- Issued
- May 10, 2003, 4:46 PM EDT (20:46 UTC)
- Expired
- May 10, 2003, 6:15 PM EDT
- In force
- 89 min
- Issued by
- the Storm Prediction Center
All 39 counties
Alamance County, NC, Caswell County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Granville County, NC, Halifax County, NC, Nash County, NC, Northampton County, NC, Orange County, NC, Person County, NC, Pitt County, NC, Rockingham County, NC, Stokes County, NC, Vance County, NC, Warren County, NC, Wilson County, NC, Bedford County, VA, Brunswick County, VA, Campbell County, VA, Charlotte County, VA, City of Danville, VA, City of Emporia, VA, City of Martinsville, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Floyd County, VA, Franklin County, VA, Greensville County, VA, Halifax County, VA, Henry County, VA, Lunenburg County, VA, Mecklenburg County, VA, Montgomery County, VA, Nottoway County, VA, Patrick County, VA, Pittsylvania County, VA, Roanoke County, VA
The radar
The Roanoke radar (KFCX), 109 km from the middle of the area, began a volume at 20:47 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, 8.8 hours before the alert went out and 79 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
- 1148 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 1374 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- -3 m²/s²
- 0-3 km storm-relative helicity
- 67 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.3
The text
As transmitted, in the capitals the NWS used until 2016.
019 ACUS11 KWNS 102047 SWOMCD SPC MCD 102046 NCZ000-VAZ000-WVZ000-102215- MESOSCALE DISCUSSION 0921 NWS STORM PREDICTION CENTER NORMAN OK 0346 PM CDT SAT MAY 10 2003 AREAS AFFECTED...SCENTRAL/SERN VA...NCENTRAL/NERN NC CONCERNING...TORNADO WATCH 340... VALID 102046Z - 102215Z SEVERAL SEVERE THUNDERSTORMS...INCLUDING A FEW SUPERCELLS WILL CONTINUE TO INTENSIFY AND TRACK ESEWD ACROSS MUCH OF WW 340 THROUGH 10/22Z. SFC WINDS WILL REMAIN BACKED ALONG A STATIONARY BOUNDARY EXTENDING FROM 45 E OF RWI TO 45 E OF DAN. ONE SUPERCELL OVER HALIFAX COUNTY IN SCENTRAL VA HAS RECENTLY MERGED WITH ANOTHER STORM. HOWEVER...STORM MOTION WILL CONTINUE TO TAKE THIS STORM ALONG THE BOUNDARY...ALLOWING FOR THE CONTINUED POTENTIAL OF ISOLATED TORNADOES IF THE STORM CAN REORGANIZE. ADDITIONAL THUNDERSTORMS MAY CONTINUE TO INTENSIFY OFF THE MTNS OF NWRN NORTH CAROLINA INTO WRN PORTIONS OF WW 340 POSING A THREAT FOR DAMAGING WINDS/LARGE HAIL IN THE NEXT 1-2 HOURS. ..CROSBIE.. 05/10/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...RNK... 36238051 37618046 37007729 35577733
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 9, 9:45 PM EDT | Mesoscale Discussion | SPC | Carteret, Craven, Duplin, Greene, Jones, Lenoir and 3 more | 60 min |
| May 10, 12:41 PM EDT | Mesoscale Discussion | SPC | Alleghany, Ashe, Avery, Mitchell, Rockingham, Stokes and 4 more | 2 hr |
| May 10, 2:31 PM EDT | Mesoscale Discussion | SPC | Alamance, Beaufort, Bertie, Caswell, Chowan, Durham and 19 more | 89 min |
| May 10, 3:15 PM EDT | Tornado Watch | SPC | Alamance, Caswell, Durham, Edgecombe, Franklin, Granville and 11 more | 6 hr |
| May 10, 7:10 PM EDT | Tornado Watch | SPC | Beaufort, Bertie, Camden, Chowan, Currituck, Dare and 20 more | 6 hr |
| May 9, 8:57 PM EDT | Mesoscale Discussion | SPC | Alleghany, Bath, Botetourt, Craig, Rockbridge, City of Buena Vista and 2 more | 63 min |
| May 10, 4:33 AM EDT | Mesoscale Discussion | SPC | Alleghany, Bath, Frederick, Highland, Rockingham, Shenandoah and 3 more | 87 min |
| May 10, 1:20 PM EDT | Tornado Watch | SPC | Bland, Buchanan, Carroll, Dickenson, Giles, Grayson and 13 more | 6 hr |
| May 10, 3:27 PM EDT | Mesoscale Discussion | SPC | Bland, Buchanan, Carroll, Dickenson, Giles, Grayson and 13 more | 93 min |
| May 10, 6:30 PM EDT | Tornado Watch | SPC | Giles | 6 hr |
Nearby
Mesoscale Discussions in Virginia, 2003Mesoscale Discussions in North Carolina, 2003Every mesoscale discussion in 2003
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.