Alert archive / Louisiana / Mesoscale Discussions in 2008

Mesoscale Discussion 2267

September 14, 20086 counties in Arkansas; 11 parishes in Louisiana; 5 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Sep 14, 2008, 1:28 AM CDT for 6 counties in Arkansas; 11 parishes in Louisiana; 5 counties in Mississippi. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Sep 14, 2008, 1:28 AM CDT (06:28 UTC)
Expired: Sep 14, 2008, 3:00 AM CDT
In force: 92 min
Issued by: the Storm Prediction Center

All 22 counties

Arkansas County, AR, Ashley County, AR, Chicot County, AR, Desha County, AR, Drew County, AR, Phillips County, AR, Caldwell Parish, LA, Catahoula Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Bolivar County, MS, Coahoma County, MS, Issaquena County, MS, Sunflower County, MS, Washington County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 161 km from the middle of the area, began a volume at 06:27 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 905Sep 14, 1:55 AM CDT

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 6.5 hours before the alert went out and 152 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: 2486 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 544 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 214 m²/s²
0-3 km storm-relative helicity: 272 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 8.9

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.

Issued	Product	Office	Counties	Lasted
Sep 13, 7:03 PM CDT	Tornado Watch	SPC	Ashley, Chicot, Columbia, Union	7 hr
Sep 13, 7:37 PM CDT	Mesoscale Discussion	SPC	Arkansas, Baxter, Boone, Bradley, Calhoun, Clark and 44 more	53 min
Sep 13, 11:03 PM CDT	Mesoscale Discussion	SPC	Arkansas, Ashley, Baxter, Boone, Bradley, Chicot and 33 more	57 min
Sep 14, 1:57 AM CDT	Tornado Watch	SPC	Ashley, Chicot, Clay, Craighead, Crittenden, Cross and 8 more	8 hr
Sep 14, 2:06 AM CDT	Mesoscale Discussion	SPC	Baxter, Boone, Fulton, Marion	84 min
Sep 14, 6:24 AM CDT	Mesoscale Discussion	SPC	Ashley, Chicot, Clay, Craighead, Crittenden, Cross and 8 more	96 min
Sep 14, 9:21 AM CDT	Mesoscale Discussion	SPC	Acadia, Avoyelles, Caldwell, Catahoula, Concordia, East Carroll and 13 more	84 min

Nearby

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