Alert archive / Mississippi / Mesoscale Discussions in 2016

Mesoscale Discussion 1849

November 29, 2016Concordia Parish, Louisiana; 11 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Nov 29, 2016, 9:47 PM CST for Concordia Parish, Louisiana; 11 counties in Mississippi. It was in force for 58 min.

The area

The outline as issued.

The facts

Issued: Nov 29, 2016, 9:47 PM CST (03:47 UTC)
Expired: Nov 29, 2016, 10:45 PM CST
In force: 58 min
Issued by: the Storm Prediction Center

Counties Concordia Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Jefferson County, MS, Lincoln County, MS, Rankin County, MS, Warren County, MS, Wilkinson County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 109 km from the middle of the area, began a volume at 03:49 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

Jackson, MS (KJAN), launched 00:00Z, 3.8 hours before the alert went out and 104 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1191 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 883 m above ground
0-6 km bulk shear: 77 kt
0-1 km storm-relative helicity: 391 m²/s²
0-3 km storm-relative helicity: 488 m²/s²
Significant tornado parameter: 3.5
Supercell composite: 15.4

Open this sounding in Storm Lab

The text

As transmitted.

078 
ACUS11 KWNS 300347
SWOMCD
SPC MCD 300347 
MSZ000-LAZ000-300445-

MESOSCALE DISCUSSION 1849
NWS STORM PREDICTION CENTER NORMAN OK
0947 PM CST TUE NOV 29 2016

AREAS AFFECTED...PORTIONS OF CENTRAL/SOUTHWEST MS INTO EASTERN LA

CONCERNING...TORNADO WATCH 508

VALID 300347Z - 300445Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 508 CONTINUES.

SUMMARY...THE RISK FOR TORNADOES -- POSSIBLY SIGNIFICANT -- IS
INCREASING ACROSS THE AREA.

DISCUSSION...DISCRETE/SEMI-DISCRETE SUPERCELL STRUCTURES ARE ONGOING
FROM NORTHEAST OF VICKSBURG MS SOUTHWESTWARD INTO EAST-CENTRAL LA...
AND ADDITIONAL CONVECTION IS DEVELOPING EASTWARD TOWARD INTERSTATE
55. ALL OF THIS ACTIVITY WILL CONTINUE TRACKING EAST-NORTHEASTWARD.
THE JACKSON MS VAD WIND PROFILE IS INDICATING AROUND 300 M2/S2 OF
0-1-KM SRH WITH AROUND 60 KT OF DEEP SHEAR. WITH AMPLE LOW-LEVEL
MOISTURE CONTINUING TO EXIST ACROSS THE AREA AIDING IN THE
MAINTENANCE OF AROUND 1000 J/KG OF MLCAPE...SUPERCELLS WITH A TORNADO
RISK WILL EXIST...AND SIGNIFICANT TORNADOES WILL BE POSSIBLE. THE
CORRIDOR AROUND THE NATCHEZ TRACE PARKWAY...AND EASTWARD TOWARD THE
INTERSTATE 55 CORRIDOR NEAR/SOUTH OF INTERSTATE 20...COULD BE A
FAVORED ZONE FOR MATURING SUPERCELL STRUCTURES CAPABLE OF TORNADOES
IN THE SHORT-TERM.

..COHEN.. 11/30/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...JAN...LIX...LCH...

LAT...LON   31399196 32299098 32559054 32569005 32348988 31389030
            30989120 31039188 31399196

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Nov 29, 6:06 PM CST	Mesoscale Discussion	SPC	Caldwell, Catahoula, Concordia, East Carroll, Franklin, Grant and 6 more	114 min
Nov 29, 8:03 PM CST	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Avoyelles, Catahoula, Concordia and 23 more	2 hr
Nov 29, 8:50 PM CST	Tornado Watch	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Catahoula and 27 more	8 hr
Nov 29, 11:37 PM CST	Mesoscale Discussion	SPC	Acadia, Ascension, Avoyelles, Catahoula, Concordia, East Baton Rouge and 18 more	113 min
Nov 30, 3:33 AM CST	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 14 more	87 min
Nov 30, 4:57 AM CST	Tornado Watch	SPC	Ascension, Assumption, East Baton Rouge, Iberia, Iberville, Jefferson and 17 more	7 hr
Nov 29, 6:43 PM CST	Mesoscale Discussion	SPC	Alcorn, Chickasaw, Clay, Itawamba, Lee, Lowndes and 6 more	92 min
Nov 30, 9:00 AM CST	Mesoscale Discussion	SPC	George, Greene, Harrison, Jackson	2 hr

Nearby

Mesoscale Discussions in Mississippi, 2016 Mesoscale Discussions in Louisiana, 2016 Every mesoscale discussion in 2016

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.