Alert archive / Arkansas / Mesoscale Discussions in 2009

Mesoscale Discussion 155

February 26, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Feb 26, 2009, 9:09 PM CST for 4 states. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Feb 26, 2009, 9:09 PM CST (03:09 UTC)
Expired: Feb 26, 2009, 10:45 PM CST
In force: 96 min
Issued by: the Storm Prediction Center

All 41 counties

Arkansas County, AR, Clay County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Grant County, AR, Greene County, AR, Jackson County, AR, Jefferson County, AR, Lee County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, St. Francis County, AR, Woodruff County, AR, Dunklin County, MO, Pemiscot County, MO, Benton County, MS, Coahoma County, MS, DeSoto County, MS, Marshall County, MS, Panola County, MS, Quitman County, MS, Tallahatchie County, MS, Tate County, MS, Tunica County, MS, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Haywood County, TN, Lake County, TN, Lauderdale County, TN, Madison County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN

The radar

The Memphis radar (KNQA), 41 km from the middle of the area, began a volume at 03:10 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 35Feb 26, 9:30 PM CST

The nearest sounding before it

Little Rock, AR (KLZK), launched 00:00Z, 3.2 hours before the alert went out and 82 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: 170 J/kg
Mixed-layer CIN: -308 J/kg
Mixed-layer LCL: 917 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 290 m²/s²
0-3 km storm-relative helicity: 332 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Feb 26, 6:12 PM CST	Severe Thunderstorm Watch	SPC	Baxter, Benton, Boone, Carroll, Clark, Cleburne and 40 more	8 hr
Feb 26, 7:42 PM CST	Mesoscale Discussion	SPC	Baxter, Boone, Carroll, Clark, Clay, Cleburne and 41 more	93 min
Feb 26, 8:29 PM CST	Mesoscale Discussion	SPC	Hempstead, Lafayette, Little River, Miller, Nevada	2 hr
Feb 26, 9:40 PM CST	Severe Thunderstorm Watch	SPC	Arkansas, Bradley, Calhoun, Clay, Cleveland, Craighead and 20 more	5 hr
Feb 26, 10:36 PM CST	Mesoscale Discussion	SPC	Arkansas, Baxter, Bradley, Calhoun, Clark, Clay and 46 more	114 min
Feb 27, 1:45 AM CST	Mesoscale Discussion	SPC	Arkansas, Cleveland, Craighead, Crittenden, Cross, Dallas and 18 more	30 min
Feb 27, 8:29 AM CST	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 10 more	31 min
Feb 27, 8:40 AM CST	Severe Thunderstorm Watch	SPC	Ashley, Bradley, Calhoun, Chicot, Cleveland, Columbia and 7 more	6 hr
Feb 27, 10:15 AM CST	Mesoscale Discussion	SPC	Ashley, Bradley, Calhoun, Chicot, Clark, Cleveland and 10 more	90 min
Feb 27, 12:16 PM CST	Mesoscale Discussion	SPC	Chicot	89 min
Feb 27, 12:38 PM CST	Tornado Watch	SPC	Ashley, Chicot	7 hr
Feb 27, 2:40 PM CST	Mesoscale Discussion	SPC	Arkansas, Clark, Cleveland, Conway, Dallas, Desha and 21 more	65 min
Feb 27, 3:38 PM CST	Mesoscale Discussion	SPC	Attala, Choctaw, Holmes, Humphreys, Kemper, Leake and 5 more	97 min
Feb 27, 5:29 PM CST	Mesoscale Discussion	SPC	Kemper, Lauderdale, Noxubee, Oktibbeha, Winston	2 hr
Feb 26, 8:46 PM CST	Severe Thunderstorm Watch	SPC	Bollinger, Butler, Cape Girardeau, Carter, Madison, Mississippi and 8 more	6 hr
Feb 27, 3:58 AM CST	Severe Thunderstorm Watch	SPC	Bedford, Cannon, Cheatham, Clay, Coffee, Cumberland and 23 more	119 min

Nearby

Mesoscale Discussions in Arkansas, 2009 Mesoscale Discussions in Tennessee, 2009 Mesoscale Discussions in Mississippi, 2009 Every mesoscale discussion in 2009

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.