Alert archive / Mississippi / Mesoscale Discussions in 2019

Mesoscale Discussion 306

April 12, 20195 parishes in Louisiana; 15 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2019, 3:20 AM CDT for 5 parishes in Louisiana; 15 counties in Mississippi. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued: Apr 12, 2019, 3:20 AM CDT (08:20 UTC)
Expired: Apr 12, 2019, 4:15 AM CDT
In force: 55 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties Avoyelles Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, Tensas Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Jefferson County, MS, Jefferson Davis County, MS, Lawrence County, MS, Lincoln County, MS, Pike County, MS, Rankin County, MS, Simpson County, MS, Warren County, MS, Wilkinson County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 129 km from the middle of the area, began a volume at 08:21 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

Slidell Radar S, LA (KSIL), launched 00:00Z, 8.3 hours before the alert went out and 199 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: 173 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 835 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 94 m²/s²
0-3 km storm-relative helicity: 97 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.2

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 12, 3:45 PM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Catahoula and 11 more	2 hr

Nearby

Mesoscale Discussions in Mississippi, 2019 Mesoscale Discussions in Louisiana, 2019 Every mesoscale discussion in 2019

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.