Alert archive / Louisiana / Mesoscale Discussions in 2016

Mesoscale Discussion 289

March 30, 20169 parishes in Louisiana

The Storm Prediction Center issued this mesoscale discussion at Mar 30, 2016, 3:53 PM CDT for 9 parishes in Louisiana. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued: Mar 30, 2016, 3:53 PM CDT (20:53 UTC)
Expired: Mar 30, 2016, 5:30 PM CDT
In force: 97 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Allen Parish, LA, Avoyelles Parish, LA, Evangeline Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Saint Landry Parish, LA, Vernon Parish, LA

The radar

The Ft Polk radar (KPOE), 47 km from the middle of the area, began a volume at 20:55 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 8.9 hours before the alert went out and 140 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: 962 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 508 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 78 m²/s²
0-3 km storm-relative helicity: 117 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.7

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 30, 2:07 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Red River and 1 more	83 min
Mar 30, 2:31 PM CDT	Tornado Watch	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 5 more	7 hr
Mar 30, 5:06 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Lincoln and 2 more	84 min
Mar 30, 6:15 PM CDT	Mesoscale Discussion	SPC	Claiborne, East Carroll, Lincoln, Morehouse, Union, West Carroll	90 min
Mar 30, 6:53 PM CDT	Tornado Watch	SPC	East Carroll, Franklin, Madison, Morehouse, Richland, Tensas and 1 more	8 hr

Nearby

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.