Alert archive / Tennessee / Mesoscale Discussions in 2012
Mesoscale Discussion 593
The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2012, 3:22 PM CDT for 5 states. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Apr 26, 2012, 3:22 PM CDT (20:22 UTC)
- Expired
- Apr 26, 2012, 4:45 PM CDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
All 83 counties
Adair County, KY, Allen County, KY, Barren County, KY, Bell County, KY, Breathitt County, KY, Clay County, KY, Clinton County, KY, Cumberland County, KY, Floyd County, KY, Harlan County, KY, Jackson County, KY, Johnson County, KY, Knott County, KY, Knox County, KY, Laurel County, KY, Lee County, KY, Leslie County, KY, Letcher County, KY, Magoffin County, KY, Martin County, KY, McCreary County, KY, Metcalfe County, KY, Monroe County, KY, Owsley County, KY, Perry County, KY, Pike County, KY, Pulaski County, KY, Rockcastle County, KY, Russell County, KY, Simpson County, KY, Wayne County, KY, Whitley County, KY, Buncombe County, NC, Graham County, NC, Haywood County, NC, Henderson County, NC, Jackson County, NC, Polk County, NC, Swain County, NC, Transylvania County, NC, Anderson County, TN, Benton County, TN, Blount County, TN, Campbell County, TN, Cheatham County, TN, Claiborne County, TN, Clay County, TN, Cocke County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Dickson County, TN, Fentress County, TN, Henry County, TN, Houston County, TN, Humphreys County, TN, Jackson County, TN, Jefferson County, TN, Knox County, TN, Loudon County, TN, Macon County, TN, Monroe County, TN, Montgomery County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Roane County, TN, Robertson County, TN, Scott County, TN, Sevier County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Union County, TN, White County, TN, Williamson County, TN, Wilson County, TN, Buchanan County, VA, Dickenson County, VA, Wise County, VA, Mingo County, WV
The radar
The Knoxville radar (KMRX), 94 km from the middle of the area, began a volume at 20:25 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 nearest sounding before it
Nashville Metro, TN (KBNA), launched 12:00Z, 8.4 hours before the alert went out and 198 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
- 824 J/kg
- Mixed-layer CIN
- -212 J/kg
- Mixed-layer LCL
- 986 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km storm-relative helicity
- 317 m²/s²
- 0-3 km storm-relative helicity
- 344 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 9.1
The text
As transmitted, in the capitals the NWS used until 2016.
966
ACUS11 KWNS 262022
SWOMCD
SPC MCD 262022
WVZ000-NCZ000-SCZ000-VAZ000-KYZ000-TNZ000-262145-
MESOSCALE DISCUSSION 0593
NWS STORM PREDICTION CENTER NORMAN OK
0322 PM CDT THU APR 26 2012
AREAS AFFECTED...SRN/ERN KY...MIDDLE/ERN TN...SWRN NC
CONCERNING...SEVERE THUNDERSTORM WATCH 191...
VALID 262022Z - 262145Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 191
CONTINUES.
GREATEST SEVERE POTENTIAL SHOULD REMAIN WITH TSTMS DEVELOPING ALONG
THE SURFACE COLD FRONT STRETCHING FROM NEAR HTS TO 40 S PAH AS OF
20Z...WITH INITIAL SUPERCELL CENTERED AROUND 30 N LOZ. STRATUS DECK
OVER NRN TN HAS BEEN ERODING AHEAD OF THE FRONT...LEAVING A 50-70 SM
WIDE ZONE OF GREATER INSOLATION. THIS WILL SUPPORT FURTHER
DESTABILIZATION JUST AHEAD OF THE ONGOING STORMS AND LIKELY RESULT
IN PROPAGATION OF A FEW SUPERCELLS ACROSS SRN KY AND EVENTUALLY INTO
NRN TN. LARGE HAIL /WITH ISOLATED SIGNIFICANT STONES/ WILL REMAIN
THE PRIMARY THREAT.
FARTHER E/SE...TSTMS HAVE PERSISTED FOR THE PAST FEW HOURS AND HAVE
RECENTLY INCREASED IN COVERAGE ACROSS THE SRN APPALACHIANS WITHIN A
WAA REGIME IN THE WAKE OF OUTFLOW FROM AN EARLIER MCV ACROSS SERN
VA...REINFORCED BY A TSTM CLUSTER APPROACHING THE NC/SC COAST. WITH
DIURNAL HEATING HAVING BEEN LIMITED BY THE ROUNDS OF
CONVECTION/PERSISTENT CLOUD COVERAGE...TSTMS WITHIN THIS ZONE SHOULD
CONTINUE TO STRUGGLE TO APPROACH SEVERE INTENSITY. STILL 40-50 KT
EFFECTIVE SHEAR MAY SUPPORT A MARGINAL HAIL THREAT WITH THE STRONGER
CORES ON THE SRN/WRN PERIPHERY OF THIS CONVECTION.
..GRAMS.. 04/26/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...RLX...GSP...MRX...JKL...LMK...OHX...PAH...MEG...
LAT...LON 36428860 36758740 37048568 37408437 37838318 38008237
37898204 37338168 36708319 36508365 36198376 35798249
35298183 35008194 35008255 35328397 35628475 35818563
35878699 35948814 36428860SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 10:11 PM CDT | Mesoscale Discussion | SPC | Anderson, Bath, Boone, Bourbon, Boyd, Boyle and 72 more | 2 hr |
| Apr 26, 12:40 AM CDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Anderson, Barren, Bourbon, Boyle and 53 more | 6 hr |
| Apr 26, 2:23 AM CDT | Mesoscale Discussion | SPC | Anderson, Barren, Boyle, Breckinridge, Bullitt, Butler and 30 more | 97 min |
| Apr 26, 4:07 AM CDT | Mesoscale Discussion | SPC | Bell, Clay, Knox, Laurel, Leslie, McCreary and 1 more | 83 min |
| Apr 26, 5:22 AM CDT | Severe Thunderstorm Watch | SPC | McCreary, Wayne, Whitley | 3 hr |
| Apr 26, 6:24 AM CDT | Mesoscale Discussion | SPC | Bell, Harlan, Leslie, Letcher, Perry | 96 min |
| Apr 26, 1:23 PM CDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bath, Bell, Boyd and 61 more | 2 hr |
| Apr 26, 2:11 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Barren, Bell, Breathitt, Calloway and 42 more | 6 hr |
| Apr 26, 5:40 PM CDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bell, Breathitt, Clay and 23 more | 95 min |
| Apr 26, 7:10 AM CDT | Severe Thunderstorm Watch | SPC | Alexander, Avery, Buncombe, Burke, Caldwell, Catawba and 19 more | 3 hr |
| Apr 26, 7:47 AM CDT | Mesoscale Discussion | SPC | Alexander, Alleghany, Ashe, Avery, Buncombe, Burke and 31 more | 88 min |
| Apr 26, 6:09 PM CDT | Mesoscale Discussion | SPC | Cherokee, Clay, Macon, Transylvania | 96 min |
| Apr 26, 4:52 PM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Chester, Crockett, Decatur, Dickson and 13 more | 83 min |
Nearby
Mesoscale Discussions in Tennessee, 2012Mesoscale Discussions in Kentucky, 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.