Alert archive / Mississippi / Mesoscale Discussions in 2016

Mesoscale Discussion 1845

November 29, 201612 parishes in Louisiana; 19 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Nov 29, 2016, 6:06 PM CST for 12 parishes in Louisiana; 19 counties in Mississippi. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued: Nov 29, 2016, 6:06 PM CST (00:06 UTC)
Expired: Nov 29, 2016, 8:00 PM CST
In force: 114 min
Issued by: the Storm Prediction Center

All 31 counties

Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Attala County, MS, Choctaw County, MS, Claiborne County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Leake County, MS, Madison County, MS, Neshoba County, MS, Noxubee County, MS, Oktibbeha County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Warren County, MS, Winston County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 66 km from the middle of the area, began a volume at 00:05 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.

Tornado Watch 508Nov 29, 8:50 PM CST

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 0.1 hours before the alert went out and 57 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.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
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, 9:47 PM CST	Mesoscale Discussion	SPC	Concordia	58 min
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.