Alert archive / Louisiana / Mesoscale Discussions in 2008

Mesoscale Discussion 934

May 15, 200817 parishes in Louisiana; Adams County, Wilkinson County, Mississippi; Jefferson County, Orange County, Texas

The Storm Prediction Center issued this mesoscale discussion at May 15, 2008, 2:11 AM CDT for 17 parishes in Louisiana; Adams County, Wilkinson County, Mississippi; Jefferson County, Orange County, Texas. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: May 15, 2008, 2:11 AM CDT (07:11 UTC)
Expired: May 15, 2008, 3:45 AM CDT
In force: 94 min
Issued by: the Storm Prediction Center

All 21 counties

Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Concordia Parish, LA, Evangeline Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Pointe Coupee Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Vermilion Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Adams County, MS, Wilkinson County, MS, Jefferson County, TX, Orange County, TX

The radar

The Lake Charles radar (KLCH), 4 km from the middle of the area, began a volume at 07:14 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.

Tornado Watch 325May 15, 4:20 AM CDT

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 7.2 hours before the alert went out and 3 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: 2367 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 569 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 57 m²/s²
0-3 km storm-relative helicity: 96 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 4.6

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.

Issued	Product	Office	Counties	Lasted
May 15, 1:16 AM CDT	Tornado Watch	SPC	Beauregard, Bienville, Bossier, Caddo, Caldwell, Claiborne and 14 more	6 hr
May 15, 4:16 AM CDT	Tornado Watch	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Calcasieu and 38 more	7 hr
May 15, 5:54 AM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Calcasieu and 29 more	96 min
May 15, 7:41 AM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 17 more	94 min
May 15, 8:42 AM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 17 more	63 min
May 15, 8:58 AM CDT	Tornado Watch	SPC	Forrest, George, Greene, Hancock, Harrison, Jackson and 5 more	6 hr
May 15, 12:28 PM CDT	Mesoscale Discussion	SPC	George, Greene, Perry, Stone, Wayne	92 min
May 14, 7:06 PM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Blanco, Brown, Burnet and 30 more	54 min
May 14, 7:50 PM CDT	Tornado Watch	SPC	Bastrop, Bell, Bosque, Brazos, Burleson, Caldwell and 30 more	6 hr
May 14, 7:53 PM CDT	Mesoscale Discussion	SPC	Brooks, Hidalgo, Jim Hogg, Starr, Zapata	67 min
May 14, 10:02 PM CDT	Mesoscale Discussion	SPC	Austin, Bandera, Bastrop, Bell, Bexar, Blanco and 76 more	88 min
May 14, 11:40 PM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Cherokee, Gregg, Henderson, Houston and 9 more	65 min
May 15, 6:24 PM CDT	Mesoscale Discussion	SPC	Dimmit, Maverick	66 min

Nearby

Mesoscale Discussions in Louisiana, 2008 Mesoscale Discussions in Mississippi, 2008 Mesoscale Discussions in Texas, 2008 Every mesoscale discussion in 2008

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.