Alert archive / Mississippi / Mesoscale Discussions in 2015

Mesoscale Discussion 2087

December 27, 20156 parishes in Louisiana; 51 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Dec 27, 2015, 3:15 PM CST for 6 parishes in Louisiana; 51 counties in Mississippi. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Dec 27, 2015, 3:15 PM CST (21:15 UTC)
Expired: Dec 27, 2015, 4:45 PM CST
In force: 90 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 57 counties

East Carroll Parish, LA, East Feliciana Parish, LA, Madison Parish, LA, Saint Helena Parish, LA, Tensas Parish, LA, Washington Parish, LA, Adams County, MS, Amite 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, Covington County, MS, Franklin County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jasper County, MS, Jefferson County, MS, Jefferson Davis County, MS, Lamar County, MS, Lawrence County, MS, Leake County, MS, Leflore County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Marion County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pike County, MS, Pontotoc County, MS, Quitman County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Sunflower County, MS, Tallahatchie County, MS, Walthall County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Wilkinson County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 22 km from the middle of the area, began a volume at 21:16 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, 9.3 hours before the alert went out and 12 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: 576 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 658 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 276 m²/s²
0-3 km storm-relative helicity: 361 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 27, 8:56 AM CST	Tornado Watch	SPC	Bossier, Caddo, De Soto, Sabine	10 hr
Dec 27, 12:45 PM CST	Mesoscale Discussion	SPC	Bossier, Caddo, De Soto, Sabine	2 hr
Dec 27, 12:47 PM CST	Mesoscale Discussion	SPC	Avoyelles, Bienville, Caldwell, Catahoula, Claiborne, Franklin and 11 more	88 min
Dec 27, 2:27 PM CST	Mesoscale Discussion	SPC	Allen, Beauregard, Bienville, Bossier, Caddo, Calcasieu and 20 more	63 min
Dec 27, 2:47 PM CST	Tornado Watch	SPC	Acadia, Allen, Beauregard, Bienville, Bossier, Caddo and 21 more	7 hr
Dec 27, 4:55 PM CST	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 13 more	2 hr

Nearby

Mesoscale Discussions in Mississippi, 2015 Mesoscale Discussions in Louisiana, 2015 Every mesoscale discussion in 2015

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.