Alert archive / Mississippi / Mesoscale Discussions in 2015

Mesoscale Discussion 372

April 19, 20154 counties in Alabama; 13 parishes in Louisiana; 20 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2015, 2:06 AM CDT for 4 counties in Alabama; 13 parishes in Louisiana; 20 counties in Mississippi. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Apr 19, 2015, 2:06 AM CDT (07:06 UTC)
Expired
Apr 19, 2015, 3:30 AM CDT
In force
84 min
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 37 counties

Choctaw County, AL, Clarke County, AL, Marengo County, AL, Washington County, AL, Ascension Parish, LA, Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, Clarke County, MS, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 7.1 hours before the alert went out and 90 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 2015-04-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 410 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 2015-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 150 square meters per square second.19395878Sfc1 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
410 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
693 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
150 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.9

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 19, 5:51 AM CDTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bullock, Butler, Coffee and 17 more114 min
Apr 19, 6:57 AM CDTTornado WatchSPCBarbour, Bullock, Butler, Chambers, Clay, Coffee and 16 more7 hr
Apr 19, 1:14 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Calhoun, Chambers, Cherokee and 36 more2 hr
Apr 19, 5:25 PM CDTMesoscale DiscussionSPCCalhoun, Cherokee, Cleburne, DeKalb, Etowah95 min
Apr 19, 2:56 AM CDTMesoscale DiscussionSPCAllen, Avoyelles, Bienville, Caldwell, Catahoula, Concordia and 11 more94 min
Apr 19, 1:52 PM CDTMesoscale DiscussionSPCAllen, Beauregard, Bienville, Bossier, Caddo, Calcasieu and 16 more53 min
Apr 19, 2:31 PM CDTSevere Thunderstorm WatchSPCAllen, Beauregard, Bienville, Bossier, Caddo, Calcasieu and 16 more7 hr
Apr 19, 4:45 PM CDTMesoscale DiscussionSPCAllen, Beauregard, Bienville, Bossier, Caddo, Calcasieu and 22 more2 hr
Apr 19, 5:46 PM CDTTornado WatchSPCBienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 20 more6 hr
Apr 19, 6:56 PM CDTMesoscale DiscussionSPCCameron64 min

Nearby

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