Alert archive / Arkansas / Mesoscale Discussions in 2017

Mesoscale Discussion 141

February 6, 201745 counties in Arkansas; 4 counties in Missouri; Dyer County, Lauderdale County, Tipton County, Tennessee

The Storm Prediction Center issued this mesoscale discussion at Feb 6, 2017, 10:31 PM CST for 45 counties in Arkansas; 4 counties in Missouri; Dyer County, Lauderdale County, Tipton County, Tennessee. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Feb 6, 2017, 10:31 PM CST (04:31 UTC)
Expired
Feb 7, 2017, 1:00 AM CST
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 52 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, Franklin County, AR, Fulton County, AR, Garland County, AR, Grant County, AR, Greene County, AR, Hot Spring County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Johnson County, AR, Lawrence County, AR, Lee County, AR, Logan County, AR, Lonoke County, AR, Marion County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Newton County, AR, Perry County, AR, Pike County, AR, Poinsett County, AR, Polk County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Randolph County, AR, Saline County, AR, Scott 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, Yell County, AR, Butler County, MO, Dunklin County, MO, Pemiscot County, MO, Ripley County, MO, Dyer County, TN, Lauderdale County, TN, Tipton County, TN

The radar

The Little Rock radar (KLZK), 52 km from the middle of the area, began a volume at 04:32 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

Little Rock, AR (KBYH), launched 00:00Z, 4.5 hours before the alert went out and 210 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, Little Rock, AR at 00:00Z on 2017-02-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 381 joules per kilogram.LCLLFCEL10008507005003002001001 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, Little Rock, AR at 00:00Z on 2017-02-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 336 square meters per square second.19395878Sfc1 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
381 J/kg
Mixed-layer CIN
-86 J/kg
Mixed-layer LCL
750 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
336 m²/s²
0-3 km storm-relative helicity
453 m²/s²
Significant tornado parameter
0.4
Supercell composite
6.3

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
Feb 6, 10:59 PM CSTSevere Thunderstorm WatchSPCBaxter, Boone, Clay, Cleburne, Conway, Craighead and 36 more9 hr
Feb 7, 1:52 AM CSTMesoscale DiscussionSPCBaxter, Clay, Cleburne, Conway, Craighead, Crittenden and 27 more113 min
Feb 7, 7:28 AM CSTMesoscale DiscussionSPCCrittenden, Lee, St. Francis2 hr
Feb 7, 4:57 PM CSTMesoscale DiscussionSPCMississippi2 hr

Nearby

Mesoscale Discussions in Arkansas, 2017Mesoscale Discussions in Missouri, 2017Mesoscale Discussions in Tennessee, 2017Every mesoscale discussion in 2017

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.