Alert archive / Mississippi / Mesoscale Discussions in 2023
Mesoscale Discussion 21
The Storm Prediction Center issued this mesoscale discussion at Jan 3, 2023, 7:56 AM CST for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 3, 2023, 7:56 AM CST (13:56 UTC)
- Expired
- Jan 3, 2023, 10:00 AM CST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 6
All 81 counties
Colbert County, AL, Franklin County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Marion County, AL, Avoyelles Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Rapides Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Adams County, MS, Alcorn County, MS, Attala County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Claiborne County, MS, Clay County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Itawamba County, MS, Jefferson County, MS, Lafayette County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Madison County, MS, Monroe County, MS, Montgomery County, MS, Oktibbeha County, MS, Pontotoc County, MS, Prentiss County, MS, Sharkey County, MS, Sunflower County, MS, Tallahatchie County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Yalobusha County, MS, Yazoo County, MS, Bedford County, TN, Cannon County, TN, Cheatham County, TN, Davidson County, TN, Decatur County, TN, DeKalb County, TN, Dickson County, TN, Giles County, TN, Hardin County, TN, Hickman County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Perry County, TN, Rutherford County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Wayne County, TN, Williamson County, TN, Wilson County, TN
The radar
The Columbus AFB radar (KGWX), 111 km from the middle of the area, began a volume at 13:59 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, 1.9 hours before the alert went out and 142 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
- 362 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 684 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- -38 m²/s²
- 0-3 km storm-relative helicity
- 4 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.3
The text
As transmitted.
735
ACUS11 KWNS 031356
SWOMCD
SPC MCD 031356
TNZ000-KYZ000-ALZ000-MSZ000-LAZ000-ARZ000-031600-
Mesoscale Discussion 0021
NWS Storm Prediction Center Norman OK
0756 AM CST Tue Jan 03 2023
Areas affected...Eastern Louisiana...Mississippi...Northwest
Alabama...Middle Tennessee...
Concerning...Tornado Watch 6...
Valid 031356Z - 031600Z
The severe weather threat for Tornado Watch 6 continues.
SUMMARY...A severe threat is expected to continue this morning from
parts of the lower Mississippi Valley northeastward into the
Tennessee Valley. Wind damage and tornadoes will be the primary
threats. A new weather watch may be needed to the east of the
current watch.
DISCUSSION...The latest regional mosaic radar imagery shows an
organized line of strong to severe storms located from eastern
Louisiana north and northeastward into western Tennessee. The
airmass ahead of this line is weakly unstable in the Tennessee
Valley and moderately unstable in the lower Mississippi Valley.
According to the RAP, MLCAPE ranges from near 500 J/kg in western
Tennessee to about 1500 J/kg in eastern Louisiana. In addition, the
line of storms is near the axis of a 50 to 60 knot low-level jet,
which is enhancing lift and shear. WSR-88D VWPs near the axis of the
jet have 0-6 km shear between 50 and 60 knots and 0-3 km
storm-relative helicity in the 300 to 400 m2/s2 range. This shear
environment will likely continue to support supercells with
wind-damage and tornado potential. The threat should gradually shift
eastward, which could necessitate watch issuance later this morning.
..Broyles.. 01/03/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LMK...OHX...BMX...HUN...MEG...JAN...LIX...LCH...
SHV...
LAT...LON 35478618 35948567 36328567 36498586 36658641 36468700
35878783 34878899 33659057 33269101 32709167 32069232
31579275 31209285 30859275 30729265 30699231 30829193
31409112 33078909 34008783 35478618SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 3, 9:14 AM CST | Tornado Watch | SPC | Autauga, Bibb, Blount, Chilton, Choctaw, Clarke and 30 more | 8 hr |
| Jan 3, 11:38 AM CST | Mesoscale Discussion | SPC | Bibb, Choctaw, Clarke, Dallas, Greene, Hale and 7 more | 97 min |
| Jan 3, 12:29 PM CST | Mesoscale Discussion | SPC | Autauga, Bullock, Butler, Calhoun, Chambers, Cherokee and 15 more | 91 min |
| Jan 3, 12:56 PM CST | Tornado Watch | SPC | Barbour, Bullock, Calhoun, Chambers, Cherokee, Clay and 13 more | 7 hr |
| Jan 3, 2:07 PM CST | Mesoscale Discussion | SPC | Autauga, Calhoun, Chambers, Chilton, Clarke, Clay and 13 more | 113 min |
| Jan 3, 2:54 PM CST | Mesoscale Discussion | SPC | Barbour, Bullock, Butler, Coffee, Conecuh, Covington and 8 more | 2 hr |
| Jan 3, 3:20 PM CST | Tornado Watch | SPC | Butler, Coffee, Conecuh, Covington, Crenshaw, Dale and 4 more | 5 hr |
| Jan 2, 6:01 PM CST | Mesoscale Discussion | SPC | Bienville, Bossier, Caddo, Claiborne, De Soto, Grant and 11 more | 89 min |
| Jan 2, 6:29 PM CST | Tornado Watch | SPC | East Carroll, Morehouse, Richland, West Carroll | 9 hr |
| Jan 2, 8:31 PM CST | Mesoscale Discussion | SPC | Bienville, Caldwell, Catahoula, Claiborne, East Carroll, Franklin and 10 more | 89 min |
| Jan 2, 8:59 PM CST | Tornado Watch | SPC | Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 8 more | 6 hr |
| Jan 2, 11:17 PM CST | Mesoscale Discussion | SPC | Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 14 more | 118 min |
| Jan 3, 1:36 AM CST | Mesoscale Discussion | SPC | Bienville, Caldwell, Catahoula, Claiborne, De Soto, East Carroll and 15 more | 114 min |
| Jan 3, 2:56 AM CST | Tornado Watch | SPC | Bienville, Bossier, Caddo, Claiborne, De Soto, East Carroll and 10 more | 8 hr |
| Jan 3, 5:01 PM CST | Severe Thunderstorm Watch | SPC | Concordia, East Feliciana, Pointe Coupee, Saint Helena, Washington, West Feliciana | 9 hr |
| Jan 2, 10:11 PM CST | Tornado Watch | SPC | Coahoma, DeSoto, Marshall, Panola, Quitman, Tate and 1 more | 5 hr |
| Jan 2, 7:09 PM CST | Mesoscale Discussion | SPC | Dyer, Lake, Obion, Weakley | 96 min |
| Jan 3, 2:08 AM CST | Mesoscale Discussion | SPC | Benton, Cheatham, Clay, Davidson, Dickson, Henry and 14 more | 3 hr |
Nearby
Mesoscale Discussions in Mississippi, 2023Mesoscale Discussions in Tennessee, 2023Mesoscale Discussions in Louisiana, 2023Every mesoscale discussion in 2023
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.