Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 585

April 26, 20118 counties in Arkansas; 5 counties in Mississippi; 5 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2011, 10:51 AM CDT for 8 counties in Arkansas; 5 counties in Mississippi; 5 counties in Tennessee. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued: Apr 26, 2011, 10:51 AM CDT (15:51 UTC)
Expired: Apr 26, 2011, 11:45 AM CDT
In force: 54 min
Issued by: the Storm Prediction Center

Counties Crittenden County, AR, Cross County, AR, Lee County, AR, Mississippi County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, St. Francis County, AR, Coahoma County, MS, DeSoto County, MS, Marshall County, MS, Tate County, MS, Tunica County, MS, Fayette County, TN, Haywood County, TN, Lauderdale County, TN, Shelby County, TN, Tipton County, TN

The radar

The Memphis radar (KNQA), 85 km from the middle of the area, began a volume at 15:53 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

Little Rock, AR (KLZK), launched 12:00Z, 3.9 hours before the alert went out and 61 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: 112 J/kg
Mixed-layer CIN: -229 J/kg
Mixed-layer LCL: 861 m above ground
0-6 km bulk shear: 70 kt
0-1 km storm-relative helicity: 88 m²/s²
0-3 km storm-relative helicity: 159 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

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
Apr 25, 7:34 PM CDT	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 33 more	116 min
Apr 25, 9:23 PM CDT	Tornado Watch	SPC	Ashley, Chicot	7 hr
Apr 25, 11:05 PM CDT	Mesoscale Discussion	SPC	Ashley, Chicot	115 min
Apr 26, 1:11 PM CDT	Mesoscale Discussion	SPC	Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 12 more	2 hr
Apr 26, 1:44 PM CDT	Tornado Watch PDS	SPC	Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 16 more	10 hr
Apr 26, 2:41 PM CDT	Mesoscale Discussion	SPC	Arkansas, Chicot, Craighead, Crittenden, Cross, Desha and 11 more	94 min
Apr 26, 3:02 PM CDT	Tornado Watch PDS	SPC	Arkansas, Ashley, Chicot, Clay, Craighead, Crittenden and 21 more	7 hr
Apr 26, 3:59 PM CDT	Mesoscale Discussion	SPC	Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 12 more	91 min
Apr 26, 5:00 PM CDT	Mesoscale Discussion	SPC	Baxter, Boone, Cleburne, Conway, Crawford, Faulkner and 19 more	30 min
Apr 26, 5:08 PM CDT	Tornado Watch	SPC	Baxter, Cleburne, Conway, Crawford, Franklin, Fulton and 15 more	5 hr
Apr 26, 6:17 PM CDT	Mesoscale Discussion	SPC	Arkansas, Baxter, Benton, Boone, Bradley, Calhoun and 63 more	118 min
Apr 26, 6:43 PM CDT	Mesoscale Discussion	SPC	Columbia, Lafayette, Little River, Miller, Union	2 hr
Apr 25, 11:42 PM CDT	Severe Thunderstorm Watch	SPC	Alcorn, Benton, Calhoun, Chickasaw, Coahoma, Itawamba and 12 more	7 hr
Apr 26, 2:04 AM CDT	Mesoscale Discussion	SPC	Bedford, Cannon, Clay, Coffee, DeKalb, Franklin and 12 more	56 min

Nearby

Mesoscale Discussions in Arkansas, 2011 Mesoscale Discussions in Mississippi, 2011 Mesoscale Discussions in Tennessee, 2011 Every mesoscale discussion in 2011

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.