Alert archive / Louisiana / Mesoscale Discussions in 2017

Mesoscale Discussion 327

March 25, 201712 parishes in Louisiana; Jefferson County, Orange County, Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 25, 2017, 2:08 AM CDT for 12 parishes in Louisiana; Jefferson County, Orange County, Texas. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued
Mar 25, 2017, 2:08 AM CDT (07:08 UTC)
Expired
Mar 25, 2017, 3:15 AM CDT
In force
67 min
Issued by
the Storm Prediction Center

Counties Acadia Parish, LA, Allen Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Evangeline Parish, LA, Grant Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Rapides Parish, LA, Saint Landry Parish, LA, Jefferson County, TX, Orange County, TX

The radar

The Lake Charles radar (KLCH), 37 km from the middle of the area, began a volume at 07:10 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 00:00Z, 7.1 hours before the alert went out and 38 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 00:00Z on 2017-03-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 762 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 00:00Z on 2017-03-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 square meters per square second.1939587897Sfc1 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
762 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.4

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.

IssuedProductOfficeCountiesLasted
Mar 24, 8:39 PM CDTMesoscale DiscussionSPCBienville, Bossier, Caddo, Claiborne, De Soto, Red River and 1 more66 min
Mar 24, 9:14 PM CDTSevere Thunderstorm WatchSPCBienville, Bossier, Caddo, Claiborne, Jackson, Lincoln and 3 more6 hr
Mar 24, 9:23 PM CDTTornado WatchSPCCaldwell, De Soto, Grant, LaSalle, Natchitoches, Red River and 2 more6 hr
Mar 24, 9:58 PM CDTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, Evangeline, Jefferson Davis, Rapides and 2 more62 min
Mar 24, 10:28 PM CDTTornado WatchSPCAllen, Beauregard, Calcasieu, Evangeline, Jefferson Davis, Rapides and 1 more6 hr
Mar 24, 11:41 PM CDTMesoscale DiscussionSPCAvoyelles, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 7 more64 min
Mar 25, 12:05 AM CDTSevere Thunderstorm WatchSPCCatahoula, Concordia, East Carroll, Franklin, Madison, Morehouse and 3 more5 hr
Mar 25, 3:06 AM CDTMesoscale DiscussionSPCCatahoula, Concordia, East Carroll, Franklin, Madison, Richland and 1 more54 min
Mar 25, 5:25 AM CDTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, Vernon2 hr
Mar 25, 12:08 PM CDTMesoscale DiscussionSPCJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 1 more3 hr
Mar 24, 7:07 PM CDTTornado WatchSPCAngelina, Austin, Brazos, Burleson, Cherokee, Colorado and 20 more5 hr

Nearby

Mesoscale Discussions in Louisiana, 2017Mesoscale Discussions in Texas, 2017Every mesoscale discussion in 2017

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.