Alert archive / Louisiana / Mesoscale Discussions in 2015

Mesoscale Discussion 1245

June 30, 201524 parishes in Louisiana; 11 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jun 30, 2015, 1:09 PM CDT for 24 parishes in Louisiana; 11 counties in Mississippi. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jun 30, 2015, 1:09 PM CDT (18:09 UTC)
Expired: Jun 30, 2015, 3:45 PM CDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 35 counties

Bienville Parish, LA, Bossier Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Tensas Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Issaquena County, MS, Jefferson County, MS, Lincoln County, MS, Warren County, MS, Wilkinson County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 160 km from the middle of the area, began a volume at 18:09 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, 6.2 hours before the alert went out and 152 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: 952 J/kg
Mixed-layer CIN: -119 J/kg
Mixed-layer LCL: 929 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 140 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Jun 30, 11:38 AM CDT	Mesoscale Discussion	SPC	East Feliciana, Saint Helena, Saint Tammany, Tangipahoa, Washington	97 min

Nearby

Mesoscale Discussions in Louisiana, 2015 Mesoscale Discussions in Mississippi, 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.