Alert archive / Louisiana / Mesoscale Discussions in 2016

Mesoscale Discussion 513

April 30, 201622 parishes in Louisiana

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2016, 10:22 AM CDT for 22 parishes in Louisiana. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued: Apr 30, 2016, 10:22 AM CDT (15:22 UTC)
Expired: Apr 30, 2016, 11:15 AM CDT
In force: 53 min
Issued by: the Storm Prediction Center

All 22 counties

Acadia Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Livingston Parish, LA, Pointe Coupee Parish, LA, Saint Charles Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, St. Mary Parish, LA, Terrebonne Parish, LA, Vermilion Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA

The radar

The Lake Charles radar (KLCH), 110 km from the middle of the area, began a volume at 15:24 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 131Apr 30, 11:30 AM CDT

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 3.4 hours before the alert went out and 109 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: 1273 J/kg
Mixed-layer CIN: -78 J/kg
Mixed-layer LCL: 690 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 249 m²/s²
0-3 km storm-relative helicity: 295 m²/s²
Significant tornado parameter: 1.3
Supercell composite: 9.9

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, 8:56 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 8 more	94 min
Apr 29, 9:58 PM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 8 more	7 hr
Apr 29, 11:42 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 5 more	93 min
Apr 30, 3:23 AM CDT	Mesoscale Discussion	SPC	Beauregard, Bienville, Bossier, Claiborne, De Soto, Lincoln and 5 more	97 min
Apr 30, 5:11 AM CDT	Severe Thunderstorm Watch	SPC	Acadia, Allen, Avoyelles, Beauregard, Bienville, Calcasieu and 22 more	9 hr
Apr 30, 7:38 AM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Beauregard, Calcasieu, Cameron, Evangeline and 2 more	67 min
Apr 30, 11:38 AM CDT	Severe Thunderstorm Watch	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 16 more	7 hr
Apr 30, 1:35 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 22 more	55 min
Apr 30, 4:00 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, Jefferson, Lafourche, Livingston, Orleans and 10 more	2 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.