Alert archive / Mississippi / Mesoscale Discussions in 2016

Mesoscale Discussion 1841

November 29, 20168 parishes in Louisiana; 23 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Nov 29, 2016, 4:20 PM CST for 8 parishes in Louisiana; 23 counties in Mississippi. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued: Nov 29, 2016, 4:20 PM CST (22:20 UTC)
Expired: Nov 29, 2016, 5:15 PM CST
In force: 55 min
Issued by: the Storm Prediction Center

All 31 counties

Caldwell Parish, LA, Catahoula Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Richland Parish, LA, Tensas Parish, LA, Attala County, MS, Carroll County, MS, Choctaw County, MS, Claiborne County, MS, Copiah County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Leake County, MS, Madison County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Oktibbeha County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Warren County, MS, Webster County, MS, Winston County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 56 km from the middle of the area, began a volume at 22:22 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 12:00Z, 10.3 hours before the alert went out and 46 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2018 m above ground
0-6 km bulk shear: 65 kt
0-1 km storm-relative helicity: 179 m²/s²
0-3 km storm-relative helicity: 254 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Nov 28, 6:36 PM CST	Mesoscale Discussion	SPC	Saint Helena, Tangipahoa, Washington	2 hr
Nov 28, 8:39 PM CST	Mesoscale Discussion	SPC	East Baton Rouge, East Feliciana, Livingston, Saint Helena, Tangipahoa, Washington and 1 more	96 min
Nov 28, 11:38 PM CST	Mesoscale Discussion	SPC	Livingston, Saint Tammany, Tangipahoa, Washington	3 hr
Nov 29, 9:51 AM CST	Mesoscale Discussion	SPC	Bienville, Caldwell, Catahoula, De Soto, Franklin, Grant and 10 more	84 min
Nov 29, 12:38 PM CST	Mesoscale Discussion	SPC	Avoyelles, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 13 more	2 hr
Nov 29, 1:48 PM CST	Tornado Watch	SPC	Caldwell, Catahoula, Concordia, East Carroll, Franklin, Grant and 12 more	7 hr
Nov 29, 5:37 PM CST	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Avoyelles, Beauregard, Calcasieu and 12 more	2 hr
Nov 29, 3:08 PM CST	Mesoscale Discussion	SPC	Alcorn, Benton, Bolivar, Calhoun, Chickasaw, Clay and 17 more	2 hr
Nov 29, 3:48 PM CST	Tornado Watch	SPC	Alcorn, Benton, Calhoun, Chickasaw, Itawamba, Lafayette and 12 more	7 hr
Nov 29, 5:24 PM CST	Mesoscale Discussion	SPC	Itawamba, Tishomingo	96 min

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.