Alert archive / Arkansas / Mesoscale Discussions in 2020

Mesoscale Discussion 361

April 12, 202045 counties in Arkansas; Adair County, Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2020, 4:44 PM CDT for 45 counties in Arkansas; Adair County, Oklahoma. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 12, 2020, 4:44 PM CDT (21:44 UTC)
Expired
Apr 12, 2020, 6:45 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 46 counties

Benton County, AR, Boone County, AR, Bradley County, AR, Calhoun County, AR, Carroll County, AR, Clark County, AR, Cleburne County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Crawford County, AR, Dallas County, AR, Faulkner County, AR, Franklin County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Jefferson County, AR, Johnson County, AR, Lincoln County, AR, Logan County, AR, Lonoke County, AR, Madison County, AR, Marion County, AR, Montgomery County, AR, Nevada County, AR, Newton County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Pope County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Stone County, AR, Union County, AR, Van Buren County, AR, Washington County, AR, White County, AR, Yell County, AR, Adair County, OK

The radar

The Little Rock radar (KLZK), 93 km from the middle of the area, began a volume at 21:44 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.

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 9.7 hours before the alert went out and 212 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-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2020-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 12:00Z on 2020-04-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
860 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
163 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 5:52 AM CDTTornado WatchSPCUnion8 hr
Apr 12, 10:24 AM CDTMesoscale DiscussionSPCAshley, Chicot96 min
Apr 12, 10:41 AM CDTTornado Watch PDSSPCAshley, Bradley, Chicot, Desha, Drew10 hr
Apr 12, 2:51 PM CDTSevere Thunderstorm WatchSPCLittle River, Miller, Sevier5 hr
Apr 12, 5:59 PM CDTSevere Thunderstorm WatchSPCArkansas, Baxter, Boone, Bradley, Calhoun, Clark and 47 more4 hr
Apr 12, 6:14 PM CDTMesoscale DiscussionSPCBoone, Calhoun, Carroll, Clark, Columbia, Conway and 29 more91 min
Apr 11, 8:57 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Cleveland, Coal, Garvin and 11 more63 min
Apr 11, 9:01 PM CDTSevere Thunderstorm WatchSPCAtoka, Bryan, Carter, Coal, Garvin, Jefferson and 6 more4 hr
Apr 11, 9:23 PM CDTMesoscale DiscussionSPCComanche, Cotton, Jackson, Tillman67 min
Apr 11, 11:41 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Coal, Garvin, Jefferson and 6 more94 min
Apr 12, 1:10 PM CDTMesoscale DiscussionSPCAdair, Atoka, Bryan, Carter, Cherokee, Choctaw and 34 more95 min

Nearby

Mesoscale Discussions in Arkansas, 2020Mesoscale Discussions in Oklahoma, 2020Every mesoscale discussion in 2020

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.