Alert archive / Louisiana / Mesoscale Discussions in 2014

Mesoscale Discussion 351

April 14, 201431 parishes in Louisiana; 13 counties in Mississippi; 6 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2014, 12:30 PM CDT for 31 parishes in Louisiana; 13 counties in Mississippi; 6 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 14, 2014, 12:30 PM CDT (17:30 UTC)
Expired
Apr 14, 2014, 2:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 50 counties

Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Richland Parish, LA, Saint Landry Parish, LA, Tensas Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Madison County, MS, Sharkey County, MS, Warren County, MS, Wilkinson County, MS, Yazoo County, MS, Chambers County, TX, Hardin County, TX, Jasper County, TX, Jefferson County, TX, Newton County, TX, Orange County, TX

The radar

The Ft Polk radar (KPOE), 40 km from the middle of the area, began a volume at 17:31 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.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 5.5 hours before the alert went out and 93 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-pSkew-T log-p diagram, Lake Charles Mun, LA at 12:00Z on 2014-04-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 585 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 12:00Z on 2014-04-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 148 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
585 J/kg
Mixed-layer CIN
-152 J/kg
Mixed-layer LCL
779 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
148 m²/s²
0-3 km storm-relative helicity
212 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.8

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.

IssuedProductOfficeCountiesLasted
Apr 13, 7:54 PM CDTMesoscale DiscussionSPCBienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more66 min
Apr 13, 11:06 PM CDTSevere Thunderstorm WatchSPCBossier, Caddo, Claiborne, Webster6 hr
Apr 14, 1:22 AM CDTMesoscale DiscussionSPCEast Carroll, Franklin, Madison, Morehouse, Ouachita, Richland and 2 more53 min
Apr 14, 1:50 AM CDTTornado WatchSPCEast Carroll, Franklin, Madison, Morehouse, Richland, Tensas and 1 more5 hr
Apr 14, 2:05 AM CDTMesoscale DiscussionSPCBossier, Caddo, Claiborne, Webster85 min
Apr 14, 4:34 AM CDTMesoscale DiscussionSPCFranklin, Madison, Richland, Tensas56 min
Apr 14, 7:42 AM CDTMesoscale DiscussionSPCBeauregard, Natchitoches, Red River, Sabine, Vernon, Winn2 hr
Apr 14, 10:34 AM CDTSevere Thunderstorm WatchSPCBienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more6 hr
Apr 14, 1:11 PM CDTSevere Thunderstorm WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 41 more10 hr
Apr 14, 3:36 PM CDTMesoscale DiscussionSPCAscension, Assumption, Jefferson, Lafourche, Livingston, Orleans and 9 more2 hr
Apr 13, 10:33 PM CDTMesoscale DiscussionSPCBolivar, Coahoma, DeSoto, Tunica57 min

Nearby

Mesoscale Discussions in Louisiana, 2014Mesoscale Discussions in Mississippi, 2014Mesoscale Discussions in Texas, 2014Every mesoscale discussion in 2014

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.