Alert archive / Arkansas / Mesoscale Discussions in 2015

Mesoscale Discussion 162

March 31, 201527 counties in Arkansas; 6 counties in Missouri; Lauderdale County, Shelby County, Tipton County, Tennessee

The Storm Prediction Center issued this mesoscale discussion at Mar 31, 2015, 2:25 PM CDT for 27 counties in Arkansas; 6 counties in Missouri; Lauderdale County, Shelby County, Tipton County, Tennessee. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Mar 31, 2015, 2:25 PM CDT (19:25 UTC)
Expired: Mar 31, 2015, 4:30 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 36 counties

Baxter County, AR, Clay County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Faulkner County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Lawrence County, AR, Marion County, AR, Mississippi County, AR, Newton County, AR, Poinsett County, AR, Pope County, AR, Randolph County, AR, Searcy County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Dunklin County, MO, Howell County, MO, Oregon County, MO, Ozark County, MO, Pemiscot County, MO, Ripley County, MO, Lauderdale County, TN, Shelby County, TN, Tipton County, TN

The radar

The Little Rock radar (KLZK), 125 km from the middle of the area, began a volume at 19:26 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 13Mar 31, 5:10 PM CDT

The nearest sounding before it

Little Rock, AR (KBYH), launched 12:00Z, 7.4 hours before the alert went out and 175 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: 836 J/kg
Mixed-layer CIN: -130 J/kg
Mixed-layer LCL: 924 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 179 m²/s²
0-3 km storm-relative helicity: 192 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.7

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
Mar 31, 12:41 PM CDT	Mesoscale Discussion	SPC	Arkansas, Desha, Grant, Jefferson, Lee, Lincoln and 5 more	94 min
Mar 31, 1:45 PM CDT	Severe Thunderstorm Watch	SPC	Arkansas, Desha, Jefferson, Lincoln, Phillips	5 hr
Mar 31, 3:57 PM CDT	Severe Thunderstorm Watch	SPC	Crawford, Franklin, Sebastian	6 hr
Mar 31, 4:32 PM CDT	Mesoscale Discussion	SPC	Phillips	58 min
Mar 31, 5:13 PM CDT	Severe Thunderstorm Watch	SPC	Clay, Cleburne, Craighead, Crittenden, Cross, Faulkner and 13 more	7 hr

Nearby

Mesoscale Discussions in Arkansas, 2015 Mesoscale Discussions in Missouri, 2015 Mesoscale Discussions in Tennessee, 2015 Every mesoscale discussion in 2015

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.