Alert archive / Mississippi / Mesoscale Discussions in 2016

Mesoscale Discussion 496

April 29, 2016East Carroll Parish, Madison Parish, Louisiana; 40 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2016, 12:37 PM CDT for East Carroll Parish, Madison Parish, Louisiana; 40 counties in Mississippi. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: Apr 29, 2016, 12:37 PM CDT (17:37 UTC)
Expired: Apr 29, 2016, 2:00 PM CDT
In force: 83 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 42 counties

East Carroll Parish, LA, Madison Parish, LA, Attala County, MS, Benton County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Copiah County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Lafayette County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Madison County, MS, Marshall County, MS, Montgomery County, MS, Neshoba County, MS, Oktibbeha County, MS, Panola County, MS, Pontotoc County, MS, Quitman County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Union County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 139 km from the middle of the area, began a volume at 17:37 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, 5.6 hours before the alert went out and 136 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: 1635 J/kg
Mixed-layer CIN: -100 J/kg
Mixed-layer LCL: 762 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 120 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 2.6

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
Apr 29, 9:46 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 10 more	89 min
Apr 29, 12:51 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, Lincoln, Union and 1 more	114 min
Apr 29, 1:43 PM CDT	Tornado Watch	SPC	Bossier, Caddo, Claiborne, Lincoln, Ouachita, Union and 1 more	8 hr
Apr 29, 5:42 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, Jackson, Lincoln and 3 more	93 min
Apr 29, 4:29 PM CDT	Mesoscale Discussion	SPC	Lowndes, Noxubee	91 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.