Alert archive / Arkansas / Mesoscale Discussions in 2018

Mesoscale Discussion 90

February 24, 20184 states

The Storm Prediction Center issued this mesoscale discussion at Feb 24, 2018, 1:39 PM CST for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Feb 24, 2018, 1:39 PM CST (19:39 UTC)
Expired
Feb 24, 2018, 3:45 PM CST
In force
2 hr
Issued by
the Storm Prediction Center
All 57 counties

Arkansas County, AR, Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Independence County, AR, Jefferson County, AR, Lafayette County, AR, Lincoln County, AR, Little River County, AR, Lonoke County, AR, Miller County, AR, Montgomery County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Sevier County, AR, Union County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Bossier Parish, LA, Caddo Parish, LA, Choctaw County, OK, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Delta County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Hopkins County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Red River County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Wood County, TX

The radar

The Western Arkansas radar (KSRX), 156 km from the middle of the area, began a volume at 19:41 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

Shreveport, LA (KBAD), launched 12:00Z, 7.7 hours before the alert went out and 163 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, Shreveport, LA at 12:00Z on 2018-02-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 659 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, Shreveport, LA at 12:00Z on 2018-02-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 220 square meters per square second.1939587897117Sfc1 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
659 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
558 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
220 m²/s²
0-3 km storm-relative helicity
273 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.3

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 24, 10:26 AM CSTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 27 more64 min
Feb 24, 11:01 AM CSTTornado WatchSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 43 more8 hr
Feb 24, 2:58 PM CSTMesoscale DiscussionSPCClay, Craighead, Greene, Mississippi62 min
Feb 24, 3:16 PM CSTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 6 more8 hr
Feb 24, 5:29 PM CSTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Chicot, Desha, Drew and 3 more91 min
Feb 24, 6:17 AM CSTMesoscale DiscussionSPCBryan, Caddo, Carter, Cleveland, Coal, Comanche and 13 more118 min
Feb 24, 4:09 AM CSTMesoscale DiscussionSPCBell, Blanco, Bosque, Brown, Burnet, Comanche and 18 more2 hr

Nearby

Mesoscale Discussions in Arkansas, 2018Mesoscale Discussions in Texas, 2018Mesoscale Discussions in Louisiana, 2018Every mesoscale discussion in 2018

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.