Alert archive / Arkansas / Mesoscale Discussions in 2009

Mesoscale Discussion 159

February 27, 200924 counties in Arkansas; Tunica County, Mississippi; Dunklin County, Missouri

The Storm Prediction Center issued this mesoscale discussion at Feb 27, 2009, 1:45 AM CST for 24 counties in Arkansas; Tunica County, Mississippi; Dunklin County, Missouri. It was in force for 30 min.

The area

The outline as issued.

The facts

Issued: Feb 27, 2009, 1:45 AM CST (07:45 UTC)
Expired: Feb 27, 2009, 2:15 AM CST
In force: 30 min
Issued by: the Storm Prediction Center

All 26 counties

Arkansas County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Grant County, AR, Greene County, AR, Hot Spring County, AR, Jackson County, AR, Jefferson County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, White County, AR, Woodruff County, AR, Dunklin County, MO, Tunica County, MS

The radar

The Little Rock radar (KLZK), 75 km from the middle of the area, began a volume at 07:48 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 00:00Z, 7.8 hours before the alert went out and 136 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, 9:09 PM CST	Mesoscale Discussion	SPC	Arkansas, Clay, Craighead, Crittenden, Cross, Grant and 12 more	96 min
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, 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

Nearby

Mesoscale Discussions in Arkansas, 2009 Mesoscale Discussions in Mississippi, 2009 Mesoscale Discussions in Missouri, 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.