Alert archive / Mississippi / Tornado Watches in 2019

Tornado Watch 708

December 29, 201916 counties in Alabama; 40 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Dec 29, 2019, 2:56 PM CST for 16 counties in Alabama; 40 counties in Mississippi. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Dec 29, 2019, 2:56 PM CST (20:56 UTC)
Expired
Dec 29, 2019, 9:00 PM CST
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt
All 56 counties

Colbert County, AL, Cullman County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Marion County, AL, Morgan County, AL, Pickens County, AL, Sumter County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Adams County, MS, Attala County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Claiborne County, MS, Clay County, MS, Copiah County, MS, Franklin County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Itawamba County, MS, Jefferson County, MS, Kemper County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Lee County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Monroe County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pontotoc County, MS, Prentiss County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Tishomingo County, MS, Warren County, MS, Webster County, MS, Winston County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 77 km from the middle of the area, began a volume at 20:59 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
50%

Warnings issued inside it

14 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Dec 29, 3:03 PM CSTSevere Thunderstorm WarningJANClaiborne, Copiah, Hinds, Jefferson42 min
Dec 29, 3:11 PM CSTSevere Thunderstorm WarningJANAttala, Holmes, Leake, Madison, Rankin, Scott and 1 more64 min
Dec 29, 3:35 PM CSTTornado WarningJANAttala, Leake, Madison40 min
Dec 29, 3:46 PM CSTSevere Thunderstorm WarningJANAttala, Choctaw, Montgomery, Webster44 min
Dec 29, 4:02 PM CSTTornado WarningJANAttala, Choctaw, Clay, Oktibbeha, Webster, Winston43 min
Dec 29, 4:42 PM CSTTornado WarningJANClay, Lowndes, Oktibbeha48 min
Dec 29, 4:52 PM CSTSevere Thunderstorm WarningMEGChickasaw, Monroe53 min
Dec 29, 5:08 PM CSTSevere Thunderstorm WarningBMXLamar, Marion52 min
Dec 29, 5:12 PM CSTSevere Thunderstorm WarningJANKemper, Lauderdale, Neshoba, Newton48 min
Dec 29, 5:18 PM CSTTornado Warning Tornado observedJANKemper, Lauderdale, Neshoba, Newton57 min
Dec 29, 5:28 PM CSTTornado WarningBMXMarion10 min
Dec 29, 5:30 PM CSTSevere Thunderstorm WarningHUNColbert, Franklin, Lawrence45 min
Dec 29, 5:34 PM CSTTornado WarningJANLowndes, Noxubee56 min
Dec 29, 6:03 PM CSTTornado WarningJANKemper, Noxubee42 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 8.9 hours before the alert went out and 79 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.

Skew-T log-pSkew-T log-p diagram, Jackson, MS at 12:00Z on 2019-12-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Jackson, MS at 12:00Z on 2019-12-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 180 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
3 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
856 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
180 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

502 
WWUS20 KWNS 292052
SEL8  
SPC WW 292052
ALZ000-MSZ000-300300-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 708
NWS Storm Prediction Center Norman OK
255 PM CST Sun Dec 29 2019

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Northwest Alabama
  Central and Northeast Mississippi

* Effective this Sunday afternoon and evening from 255 PM until
  900 PM CST.

* Primary threats include...
  A few tornadoes possible
  Scattered damaging wind gusts to 70 mph possible

SUMMARY...An increasingly organized cluster of thunderstorms over
western Mississippi will track rapidly northeastward across the
watch area this afternoon and evening.  Damaging winds and a few
tornadoes are possible with the more intense cells.

The tornado watch area is approximately along and 60 statute miles
east and west of a line from 35 miles east southeast of Natchez MS
to 30 miles northeast of Muscle Shoals AL. For a complete depiction
of the watch see the associated watch outline update (WOUS64 KWNS
WOU8).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean
storm motion vector 24050.

...Hart

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 29, 4:47 PM CSTMesoscale DiscussionSPCFayette, Franklin, Lamar, Lawrence, Marion, Winston88 min
Dec 29, 12:58 PM CSTMesoscale DiscussionSPCAvoyelles, Catahoula, Concordia, Evangeline, Franklin, LaSalle and 3 more3 hr
Dec 29, 3:36 PM CSTMesoscale DiscussionSPCAttala, Choctaw, Leake, Madison, Neshoba, Oktibbeha and 2 more54 min

Nearby

Tornado Watches in Mississippi, 2019Tornado Watches in Alabama, 2019Every tornado watch in 2019

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.