Alert archive / Louisiana / Mesoscale Discussions in 2008

Mesoscale Discussion 935

May 15, 2008Ashley County, Chicot County, Drew County, Arkansas; 35 parishes in Louisiana; 32 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 15, 2008, 5:54 AM CDT for Ashley County, Chicot County, Drew County, Arkansas; 35 parishes in Louisiana; 32 counties in Mississippi. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: May 15, 2008, 5:54 AM CDT (10:54 UTC)
Expired: May 15, 2008, 7:30 AM CDT
In force: 96 min
Issued by: the Storm Prediction Center

All 70 counties

Ashley County, AR, Chicot County, AR, Drew County, AR, Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Livingston Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Richland Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, Vermilion Parish, LA, West Baton Rouge Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Attala County, MS, Carroll County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Jefferson Davis County, MS, Lawrence County, MS, Leake County, MS, Leflore County, MS, Lincoln County, MS, Madison County, MS, Neshoba County, MS, Newton County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Sunflower County, MS, Walthall County, MS, Warren County, MS, Washington County, MS, Wilkinson County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 133 km from the middle of the area, began a volume at 10:56 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

Jackson, MS (KJAN), launched 00:00Z, 10.9 hours before the alert went out and 125 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: 645 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 536 m above ground
0-6 km bulk shear: 66 kt
0-1 km storm-relative helicity: 258 m²/s²
0-3 km storm-relative helicity: 407 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 3.3

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	Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 10 more	6 hr
May 15, 4:16 AM CDT	Tornado Watch	SPC	Ashley, Chicot, Desha, Drew, Lincoln	7 hr
May 15, 2:11 AM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Cameron and 11 more	94 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

Nearby

Mesoscale Discussions in Louisiana, 2008 Mesoscale Discussions in Mississippi, 2008 Mesoscale Discussions in Arkansas, 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.