Alert archive / Mississippi / Mesoscale Discussions in 2017

Mesoscale Discussion 245

March 1, 20178 parishes in Louisiana; 20 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Mar 1, 2017, 1:32 PM CST for 8 parishes in Louisiana; 20 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Mar 1, 2017, 1:32 PM CST (19:32 UTC)
Expired: Mar 1, 2017, 4:00 PM CST
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 28 counties

Acadia Parish, LA, Avoyelles Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Pointe Coupee Parish, LA, Saint Helena Parish, LA, Saint Landry Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Clarke County, MS, Copiah County, MS, Covington County, MS, Franklin County, MS, Jasper County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Pike County, MS, Simpson County, MS, Smith County, MS, Walthall County, MS, Wayne County, MS, Wilkinson County, MS

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 7.5 hours before the alert went out and 127 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: 253 J/kg
Mixed-layer CIN: -243 J/kg
Mixed-layer LCL: 753 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 295 m²/s²
0-3 km storm-relative helicity: 396 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.5

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
Mar 1, 2:09 AM CST	Mesoscale Discussion	SPC	DeSoto, Tunica	2 hr
Mar 1, 4:19 AM CST	Mesoscale Discussion	SPC	Alcorn	56 min
Mar 1, 10:08 AM CST	Mesoscale Discussion	SPC	Alcorn, Attala, Benton, Bolivar, Calhoun, Carroll and 38 more	2 hr
Mar 1, 11:48 AM CST	Tornado Watch	SPC	Attala, Calhoun, Carroll, Chickasaw, Choctaw, Clay and 19 more	6 hr
Mar 1, 2:11 PM CST	Mesoscale Discussion	SPC	Kemper, Leake, Lowndes, Neshoba, Noxubee, Winston	2 hr
Mar 1, 5:54 PM CST	Mesoscale Discussion	SPC	Clarke, Jones, Wayne	2 hr

Nearby

Mesoscale Discussions in Mississippi, 2017 Mesoscale Discussions in Louisiana, 2017 Every mesoscale discussion in 2017

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.