Alert archive / Mississippi / Mesoscale Discussions in 2014

Mesoscale Discussion 305

April 6, 20149 parishes in Louisiana; 14 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 6, 2014, 11:49 PM CDT for 9 parishes in Louisiana; 14 counties in Mississippi. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued
Apr 6, 2014, 11:49 PM CDT (04:49 UTC)
Expired
Apr 7, 2014, 1:15 AM CDT
In force
86 min
Issued by
the Storm Prediction Center
All 23 counties

Ascension Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Livingston Parish, LA, Saint Helena Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, Amite County, MS, Covington County, MS, Forrest County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Pike County, MS, Simpson County, MS, Smith County, MS, Walthall County, MS

The watches that followed

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

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 4.8 hours before the alert went out and 114 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, Slidell Radar S, LA at 00:00Z on 2014-04-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1102 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, Slidell Radar S, LA at 00:00Z on 2014-04-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 330 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
1102 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
542 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
330 m²/s²
0-3 km storm-relative helicity
422 m²/s²
Significant tornado parameter
2.7
Supercell composite
11.7

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 6, 7:48 PM CDTMesoscale DiscussionSPCAcadia, Calcasieu, Cameron, Evangeline, Jefferson Davis, Lafayette and 2 more87 min
Apr 6, 10:10 PM CDTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 18 more2 hr
Apr 6, 10:40 PM CDTMesoscale DiscussionSPCAcadia, Iberia, Lafayette, Saint Landry, Saint Martin, St. Mary and 1 more65 min
Apr 7, 12:50 AM CDTMesoscale DiscussionSPCAscension, Assumption, Jefferson, Lafourche, Livingston, Orleans and 9 more25 min
Apr 7, 1:16 AM CDTTornado WatchSPCAscension, Assumption, East Baton Rouge, East Feliciana, Jefferson, Lafourche and 12 more7 hr
Apr 7, 3:16 AM CDTMesoscale DiscussionSPCOrleans, Saint Bernard, Saint Charles, Saint James, Saint John the Baptist, Saint Tammany and 2 more119 min
Apr 7, 5:42 AM CDTMesoscale DiscussionSPCAscension, Assumption, Jefferson, Lafourche, Livingston, Orleans and 7 more2 hr
Apr 6, 8:02 PM CDTMesoscale DiscussionSPCAttala, Choctaw, Clay, Kemper, Lowndes, Monroe and 6 more118 min
Apr 6, 11:42 PM CDTMesoscale DiscussionSPCKemper, Leake, Neshoba, Noxubee2 hr

Nearby

Mesoscale Discussions in Mississippi, 2014Mesoscale Discussions in Louisiana, 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.