Alert archive / Tennessee / Mesoscale Discussions in 2011
Mesoscale Discussion 970
The Storm Prediction Center issued this mesoscale discussion at May 25, 2011, 7:22 PM CDT for 4 states. It was in force for 53 min.
The area
The outline as issued.
The facts
- Issued
- May 25, 2011, 7:22 PM CDT (00:22 UTC)
- Expired
- May 25, 2011, 8:15 PM CDT
- In force
- 53 min
- Issued by
- the Storm Prediction Center
All 50 counties
Ashley County, AR, Bradley County, AR, Chicot County, AR, Desha County, AR, Drew County, AR, Lincoln County, AR, Phillips County, AR, Union County, AR, Union Parish, LA, Alcorn County, MS, Benton County, MS, Bolivar County, MS, Coahoma County, MS, DeSoto County, MS, Lafayette County, MS, Marshall County, MS, Panola County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tunica County, MS, Union County, MS, Washington County, MS, Yalobusha County, MS, Benton County, TN, Carroll County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Houston County, TN, Humphreys County, TN, Lauderdale County, TN, Madison County, TN, McNairy County, TN, Montgomery County, TN, Perry County, TN, Shelby County, TN, Stewart County, TN, Tipton County, TN, Weakley County, TN
The radar
The Memphis radar (KNQA), 58 km from the middle of the area, began a volume at 00:23 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
Little Rock, AR (KLZK), launched 00:00Z, 0.4 hours before the alert went out and 4 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
- 2 J/kg
- Mixed-layer CIN
- -10 J/kg
- Mixed-layer LCL
- 2470 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- 65 m²/s²
- 0-3 km storm-relative helicity
- 163 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
The text
As transmitted, in the capitals the NWS used until 2016.
067
ACUS11 KWNS 260023
SWOMCD
SPC MCD 260022
TNZ000-KYZ000-MSZ000-ARZ000-LAZ000-260115-
MESOSCALE DISCUSSION 0970
NWS STORM PREDICTION CENTER NORMAN OK
0722 PM CDT WED MAY 25 2011
AREAS AFFECTED...ERN AR...NRN MS...WRN TN
CONCERNING...TORNADO WATCH 374...
VALID 260022Z - 260115Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 374 CONTINUES.
THREAT OF TORNADOES...DMGG WINDS...AND LARGE HAIL PERSISTS OVER
PORTIONS OF ERN AR...NRN MS AND WRN TN.
NUMEROUS DISCRETE SUPERCELLS HAVE DEVELOPED ACROSS THE WATCH
AREA...WITH STORM INTERACTIONS LEADING TO A MORE BROKEN
LINE/CLUSTERS OF STORMS WITH EMBEDDED STRONGER CIRCULATIONS. 00Z
SOUNDING AT NASHVILLE SHOWS A SUBTLE WARM LAYER AT 700 MB THAT HAS
BEEN INHIBITING WARM SECTOR DEVELOPMENT AHEAD OF THE MAIN AREA OF
CONVECTION...NOW LOCATED JUST EAST OF THE AR/MS/TN BORDER.
HOWEVER...SHORT-LIVED CELLS IN NERN MS AND CNTRL TN SUGGEST THAT AS
STRONGER UPPER FORCING APPROACHES AND THE LOW LEVEL JET CONTINUES TO
DEVELOP EWD...A FEW DISCRETE SUPERCELLS MAY BE POSSIBLE IN ADVANCE
OF A POTENTIALLY MORE WIDESPREAD WIND AND HAIL THREAT.
..HURLBUT.. 05/26/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...PAH...MEG...JAN...LZK...SHV...
LAT...LON 36598728 35118812 33848988 32959151 32639273 33169306
34779063 36128957 36458897 36598728SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 25, 7:45 PM CDT | Mesoscale Discussion | SPC | Bienville, Caldwell, De Soto, Grant, Jackson, Lincoln and 9 more | 60 min |
| May 25, 9:43 PM CDT | Tornado Watch | SPC | Avoyelles, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 14 more | 5 hr |
| May 26, 2:05 AM CDT | Mesoscale Discussion | SPC | Ascension, East Baton Rouge, East Feliciana, Iberville, Livingston, Orleans and 10 more | 85 min |
| May 26, 5:18 PM CDT | Mesoscale Discussion | SPC | Orleans, Saint Bernard, Saint Tammany | 57 min |
| May 25, 8:33 PM CDT | Tornado Watch | SPC | Alcorn, Benton, Calhoun, Chickasaw, DeSoto, Itawamba and 14 more | 7 hr |
| May 25, 10:27 PM CDT | Mesoscale Discussion | SPC | Attala, Calhoun, Carroll, Chickasaw, Choctaw, Clay and 14 more | 2 hr |
| May 26, 7:56 AM CDT | Mesoscale Discussion | SPC | Lowndes | 94 min |
| May 26, 12:22 PM CDT | Mesoscale Discussion | SPC | Clarke, Covington, Forrest, George, Greene, Jasper and 6 more | 83 min |
| May 26, 9:15 AM CDT | Severe Thunderstorm Watch | SPC | Anderson, Bledsoe, Blount, Bradley, Campbell, Carter and 30 more | 9 hr |
| May 26, 2:09 PM CDT | Mesoscale Discussion | SPC | Clay, Fentress, Jackson, Overton, Pickett, Scott and 1 more | 96 min |
| May 26, 2:32 PM CDT | Mesoscale Discussion | SPC | Carter, Cocke, Greene, Hamblen, Jefferson, Sevier and 3 more | 58 min |
| May 26, 3:36 PM CDT | Mesoscale Discussion | SPC | Carter, Cocke, Greene, Hawkins, Johnson, Sullivan and 2 more | 84 min |
| May 26, 4:10 PM CDT | Severe Thunderstorm Watch | SPC | Anderson, Bledsoe, Blount, Bradley, Campbell, Carter and 27 more | 7 hr |
Nearby
Mesoscale Discussions in Tennessee, 2011Mesoscale Discussions in Mississippi, 2011Mesoscale Discussions in Arkansas, 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.