Alert archive / Tennessee / Mesoscale Discussions in 2011
Mesoscale Discussion 967
The Storm Prediction Center issued this mesoscale discussion at May 25, 2011, 5:56 PM CDT for 4 states. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- May 25, 2011, 5:56 PM CDT (22:56 UTC)
- Expired
- May 25, 2011, 7:00 PM CDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
All 48 counties
Arkansas County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Greene County, AR, Lee County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, St. Francis County, AR, Dunklin County, MO, Pemiscot County, MO, Alcorn County, MS, Benton County, MS, Coahoma County, MS, DeSoto County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Marshall County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Carroll County, TN, Chester County, TN, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Madison County, TN, McNairy County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN
The radar
The Memphis radar (KNQA), 14 km from the middle of the area, began a volume at 22:57 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 12:00Z, 10.9 hours before the alert went out and 44 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
- 2124 J/kg
- Mixed-layer CIN
- -14 J/kg
- Mixed-layer LCL
- 600 m above ground
- 0-6 km bulk shear
- 69 kt
- 0-1 km storm-relative helicity
- 445 m²/s²
- 0-3 km storm-relative helicity
- 413 m²/s²
- Significant tornado parameter
- 6.0
- Supercell composite
- 20.1
The text
As transmitted, in the capitals the NWS used until 2016.
046
ACUS11 KWNS 252256
SWOMCD
SPC MCD 252256
TNZ000-KYZ000-MSZ000-MOZ000-ARZ000-260000-
MESOSCALE DISCUSSION 0967
NWS STORM PREDICTION CENTER NORMAN OK
0556 PM CDT WED MAY 25 2011
AREAS AFFECTED...ERN AR/WRN TN/NRN MS
CONCERNING...TORNADO WATCH 371...
VALID 252256Z - 260000Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 371 CONTINUES.
A THREAT OF LONG-TRACKED...STRONG TORNADOES IS PERSISTING OVER
PORTIONS OF ERN AR...PROGRESSING ENEWD INTO WRN TN AND NRN
MS...WHILE RIGHT-SPLITS WILL PROGRESS DUE EAST.
A SERIES OF DISCRETE SUPERCELLS ARE PERSISTING AHEAD OF AN EFFECTIVE
DRYLINE/FRONTAL MERGER EXTENDING FROM A SURFACE LOW IN NERN MO...SWD
THROUGH ERN AR...AND SWWD THROUGH TX. GIVEN THE EXPANSIVE WARM
SECTOR CHARACTERIZED BY MID TO UPPER 80S TEMPERATURES IN CONJUNCTION
WITH UPPER 60S DEW POINTS...THE ORIENTATION OF A STRONG SLY LOW
LEVEL JET /50 KTS AT 1 KFT AT MEMPHIS VAD/ PERSISTING AFTER SUNSET
WILL MAINTAIN AN INFLUX OF HIGHER THETA-E AIR. THIS WILL ALLOW
DANGEROUS STORMS TO CONTINUE. DEEP LAYER SHEAR VECTORS ORTHOGONAL TO
THE AFOREMENTIONED SURFACE BOUNDARIES AND SUBSTANTIALLY VEERING
WINDS WITH HEIGHT WILL REMAIN CONDUCIVE TO DISCRETE SUPERCELLS
CAPABLE OF PRODUCING LONG-TRACKED/STRONG TORNADOES.
..HURLBUT.. 05/25/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...PAH...MEG...JAN...LZK...
LAT...LON 34188823 34009200 34399189 35659075 36359051 36538903
36498816 34188823SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 24, 7:42 PM CDT | Mesoscale Discussion | SPC | Benton, Crawford, Little River, Polk, Scott, Sebastian and 2 more | 63 min |
| May 24, 8:05 PM CDT | Tornado Watch | SPC | Baxter, Benton, Boone, Carroll, Clark, Conway and 30 more | 7 hr |
| May 24, 11:24 PM CDT | Mesoscale Discussion | SPC | Baxter, Boone, Carroll, Clark, Conway, Franklin and 21 more | 96 min |
| May 25, 12:48 AM CDT | Mesoscale Discussion | SPC | Clay, Craighead, Fulton, Greene, Independence, Jackson and 4 more | 57 min |
| May 25, 7:31 AM CDT | Mesoscale Discussion | SPC | Clay, Craighead, Crittenden, Cross, Greene, Mississippi and 1 more | 59 min |
| May 25, 9:54 AM CDT | Mesoscale Discussion | SPC | Baxter, Boone, Carroll, Clay, Cleburne, Conway and 33 more | 96 min |
| May 25, 10:18 AM CDT | Mesoscale Discussion | SPC | Fulton, Independence, Izard, Jackson, St. Francis, Sharp and 2 more | 57 min |
| May 25, 10:37 AM CDT | Tornado Watch | SPC | Baxter, Boone, Carroll, Fulton, Izard, Madison and 5 more | 7 hr |
| May 25, 11:02 AM CDT | Mesoscale Discussion | SPC | Clay | 28 min |
| May 25, 11:52 AM CDT | Mesoscale Discussion | SPC | Arkansas, Clark, Clay, Cleburne, Cleveland, Conway and 38 more | 83 min |
| May 25, 12:28 PM CDT | Tornado Watch | SPC | Arkansas, Baxter, Bradley, Calhoun, Clark, Clay and 41 more | 8 hr |
| May 25, 1:53 PM CDT | Mesoscale Discussion | SPC | Bradley, Calhoun, Clark, Columbia, Dallas, Hempstead and 9 more | 2 hr |
| May 25, 2:56 PM CDT | Mesoscale Discussion | SPC | Arkansas, Calhoun, Clark, Clay, Cleburne, Cleveland and 33 more | 94 min |
| May 25, 3:10 PM CDT | Mesoscale Discussion | SPC | Clay | 95 min |
| May 25, 3:16 PM CDT | Tornado Watch | SPC | Ashley, Chicot, Columbia, Lafayette, Miller, Nevada and 1 more | 7 hr |
| May 24, 7:07 PM CDT | Mesoscale Discussion | SPC | Andrew, Barton, Bates, Buchanan, Cass, Cedar and 14 more | 53 min |
| May 24, 7:26 PM CDT | Tornado Watch | SPC | Adair, Barry, Barton, Bates, Benton, Buchanan and 48 more | 7 hr |
| May 25, 1:22 AM CDT | Tornado Watch | SPC | Audrain, Boone, Callaway, Camden, Christian, Clark and 43 more | 7 hr |
| May 25, 4:58 AM CDT | Mesoscale Discussion | SPC | Crawford, Dent, Franklin, Iron, Jefferson, Reynolds and 7 more | 92 min |
| May 25, 5:46 AM CDT | Tornado Watch | SPC | Perry | 7 hr |
| May 25, 11:09 AM CDT | Tornado Watch | SPC | Bollinger, Butler, Cape Girardeau, Carter, Franklin, Iron and 19 more | 10 hr |
| May 25, 1:28 PM CDT | Mesoscale Discussion | SPC | Adair, Audrain, Boone, Caldwell, Callaway, Camden and 44 more | 92 min |
| May 25, 2:31 PM CDT | Tornado Watch | SPC | Clark, Scotland | 7 hr |
| May 25, 2:32 PM CDT | Mesoscale Discussion | SPC | Audrain, Lincoln, Marion, Monroe, Montgomery, Pike and 2 more | 58 min |
| May 25, 6:25 PM CDT | Mesoscale Discussion | SPC | Bollinger, Butler, Cape Girardeau, Mississippi, Perry, Scott and 2 more | 2 hr |
| May 25, 3:45 PM CDT | Mesoscale Discussion | SPC | Bedford, Benton, Cannon, Cheatham, Coffee, Davidson and 24 more | 90 min |
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.