Alert archive / North Carolina / Mesoscale Discussions in 2003
Mesoscale Discussion 2170
The Storm Prediction Center issued this mesoscale discussion at Aug 17, 2003, 12:06 PM EDT for 4 states. It was in force for 114 min.
The area
The outline as issued.
The facts
- Issued
- Aug 17, 2003, 12:06 PM EDT (16:06 UTC)
- Expired
- Aug 17, 2003, 2:00 PM EDT
- In force
- 114 min
- Issued by
- the Storm Prediction Center
All 71 counties
Bell County, KY, Breathitt County, KY, Clay County, KY, Estill County, KY, Floyd County, KY, Harlan County, KY, Jackson County, KY, Knott County, KY, Knox County, KY, Laurel County, KY, Lee County, KY, Leslie County, KY, Letcher County, KY, Owsley County, KY, Perry County, KY, Whitley County, KY, Alamance County, NC, Alexander County, NC, Alleghany County, NC, Ashe County, NC, Avery County, NC, Caldwell County, NC, Caswell County, NC, Chatham County, NC, Davidson County, NC, Davie County, NC, Forsyth County, NC, Guilford County, NC, Iredell County, NC, Mitchell County, NC, Orange County, NC, Person County, NC, Randolph County, NC, Rockingham County, NC, Rowan County, NC, Stokes County, NC, Surry County, NC, Watauga County, NC, Wilkes County, NC, Yadkin County, NC, Carter County, TN, Claiborne County, TN, Greene County, TN, Hancock County, TN, Hawkins County, TN, Johnson County, TN, Sullivan County, TN, Unicoi County, TN, Washington County, TN, Bland County, VA, Buchanan County, VA, Carroll County, VA, City of Bristol, VA, City of Danville, VA, City of Galax, VA, City of Martinsville, VA, City of Norton, VA, Dickenson County, VA, Floyd County, VA, Grayson County, VA, Henry County, VA, Lee County, VA, Patrick County, VA, Pulaski County, VA, Russell County, VA, Scott County, VA, Smyth County, VA, Tazewell County, VA, Washington County, VA, Wise County, VA, Wythe County, VA
The radar
The Knoxville radar (KMRX), 122 km from the middle of the area, began a volume at 16:09 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, 4.1 hours before the alert went out and 226 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
- 994 J/kg
- Mixed-layer CIN
- -68 J/kg
- Mixed-layer LCL
- 1043 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- -1 m²/s²
- 0-3 km storm-relative helicity
- 1 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
812 ACUS11 KWNS 171607 SWOMCD SPC MCD 171606 VAZ000-NCZ000-WVZ000-TNZ000-KYZ000-171800- MESOSCALE DISCUSSION 2170 NWS STORM PREDICTION CENTER NORMAN OK 1106 AM CDT SUN AUG 17 2003 AREAS AFFECTED...ERN KY / SRN VA / WRN-CNTRL NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 171606Z - 171800Z DEVELOPING TSTMS OVER ERN KY INTO FAR WRN VA ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE AFTERNOON HOURS WITH THE POTENTIAL FOR WIND/HAIL WITH THE STRONGEST CELLS. CONVECTIVE TRENDS WILL BE MONITORED FOR A POSSIBLE SEVERE TSTM WATCH THIS AFTERNOON. AS OF 1545Z...VISIBLE SATELLITE IMAGERY AND REGIONAL RADAR DATA SHOWED TSTMS BEGINNING TO DEVELOP OVER PORTIONS OF ERN KY / S/SE OF JKL / INTO FAR WRN VA AND NERN TN. IT APPEARS THAT THESE STORMS ARE DEVELOPING INVOF A WEAK FRONTAL ZONE THAT EXTENDED FROM CNTRL VA WWD THROUGH CNTRL KY TO AN AREA OF LOW PRESSURE OVER S-CNTRL IL PER 15Z MESOANALYSIS. WATER VAPOR IMAGERY ALSO SUGGESTS THAT THIS AREA MAY BE UNDER THE INFLUENCE OF AN AREA OF MESOSCALE ASCENT TO THE S OF A VORTICITY CENTER MOVING INTO WRN VA. DIABATIC HEATING ALONG AND S OF THIS FRONTAL BOUNDARY COUPLED WITH MOIST BOUNDARY-LAYER CONDITIONS / I.E. DEWPOINTS IN THE LOWER 70S / WILL CONTRIBUTE TO A MODERATELY UNSTABLE AIRMASS THIS AFTERNOON WITH MLCAPES OF 1500-2500 J/KG. MOREOVER...A 70-80KT UPPER-LEVEL JET IS FORECAST TO TRANSLATE SLOWLY SEWD ACROSS THE FRONTAL ZONE INTO THE WARM SECTOR OVER NC...PROVIDING SUFFICIENT DEEP-LAYER SHEAR FOR ORGANIZED SEVERE TSTMS WITH THE POTENTIAL FOR LARGE HAIL/DAMAGING WINDS. CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED AND A SEVERE TSTM WATCH MAY BE REQUIRED LATER THIS AFTERNOON. ..MEAD.. 08/17/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...RAH...RNK...RLX...GSP...MRX...JKL...LMK... 37728423 37648305 36557862 35377931 35888217 36598429
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 17, 1:15 PM EDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Barren, Bell, Boyle, Breckinridge and 33 more | 6 hr |
| Aug 17, 2:48 PM EDT | Mesoscale Discussion | SPC | Ballard, Caldwell, Carlisle, Crittenden, Graves, Henderson and 9 more | 117 min |
| Aug 17, 4:10 PM EDT | Severe Thunderstorm Watch | SPC | Ballard, Caldwell, Calloway, Carlisle, Christian, Crittenden and 16 more | 6 hr |
| Aug 17, 4:27 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bell, Boyle, Breckinridge and 37 more | 2 hr |
| Aug 17, 6:16 PM EDT | Mesoscale Discussion | SPC | Bell, Clay, Harlan, Jackson, Knox, Laurel and 9 more | 59 min |
| Aug 17, 7:51 PM EDT | Mesoscale Discussion | SPC | Caldwell, Calloway, Carlisle, Christian, Crittenden, Fulton and 12 more | 54 min |
| Aug 17, 1:52 PM EDT | Mesoscale Discussion | SPC | Alamance, Alexander, Alleghany, Bertie, Cabarrus, Caswell and 40 more | 113 min |
| Aug 17, 2:20 PM EDT | Severe Thunderstorm Watch | SPC | Alamance, Alexander, Alleghany, Ashe, Burke, Cabarrus and 40 more | 6 hr |
| Aug 17, 6:25 PM EDT | Mesoscale Discussion | SPC | Alamance, Alexander, Alleghany, Anson, Ashe, Bertie and 54 more | 2 hr |
Nearby
Mesoscale Discussions in North Carolina, 2003Mesoscale Discussions in Virginia, 2003Mesoscale Discussions in Kentucky, 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.