Alert archive / Arkansas / Mesoscale Discussions in 2021
Mesoscale Discussion 343
The Storm Prediction Center issued this mesoscale discussion at Apr 9, 2021, 2:50 PM CDT for 24 counties in Arkansas; 24 counties in Missouri; Ottawa County, Oklahoma. It was in force for 85 min.
The area
The outline as issued.
The facts
- Issued
- Apr 9, 2021, 2:50 PM CDT (19:50 UTC)
- Expired
- Apr 9, 2021, 4:15 PM CDT
- In force
- 85 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 60%
All 49 counties
Baxter County, AR, Benton County, AR, Boone County, AR, Carroll County, AR, Clay County, AR, Cleburne County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Lawrence County, AR, Madison County, AR, Marion County, AR, Mississippi County, AR, Newton County, AR, Poinsett County, AR, Randolph County, AR, Searcy County, AR, Sharp County, AR, Stone County, AR, Barry County, MO, Butler County, MO, Carter County, MO, Christian County, MO, Dade County, MO, Douglas County, MO, Dunklin County, MO, Greene County, MO, Howell County, MO, Jasper County, MO, Lawrence County, MO, McDonald County, MO, Newton County, MO, Oregon County, MO, Ozark County, MO, Reynolds County, MO, Ripley County, MO, Shannon County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Wayne County, MO, Webster County, MO, Wright County, MO, Ottawa County, OK
The radar
The Springfield radar (KSGF), 102 km from the middle of the area, began a volume at 19:51 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, 7.8 hours before the alert went out and 109 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.
- Mixed-layer CAPE
- 107 J/kg
- Mixed-layer CIN
- -149 J/kg
- Mixed-layer LCL
- 1650 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 415 m²/s²
- 0-3 km storm-relative helicity
- 429 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.8
The text
As transmitted.
699
ACUS11 KWNS 091950
SWOMCD
SPC MCD 091950
MOZ000-TNZ000-ARZ000-OKZ000-KSZ000-092115-
Mesoscale Discussion 0343
NWS Storm Prediction Center Norman OK
0250 PM CDT Fri Apr 09 2021
Areas affected...northern Arkansas/southern Missouri
Concerning...Severe potential...Watch possible
Valid 091950Z - 092115Z
Probability of Watch Issuance...60 percent
SUMMARY...Thunderstorms continue to increase on the northern fringe
of the ongoing convective cluster crossing Arkansas/the Arklatex.
Local risk for damaging winds and/or hail may warrant WW issuance.
DISCUSSION...Latest radar loop shows a band of strong storms moving
slowly northward across northern Arkansas, on the northern fringe of
the larger convective cluster farther south. Meanwhile, additional
convective development is evident over adjacent southwestern
Missouri.
With some destabilization having occurred with afternoon heating
just north of the convective cloud shield, mixed-layer cape 1000 to
1500 J/kg is indicated. As mid-level southwesterly flow increases
with the approach of the short-wave trough moving out of the central
High Plains, shear will likely support stronger/occasionally severe
storms into the evening. With locally damaging winds possible,
along with local hail potential, a WW is being considered for this
region.
..Goss/Thompson.. 04/09/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...MEG...LSX...LZK...SGF...TSA...ICT...
LAT...LON 37069508 37429401 37669277 37439063 36278983 35159026
35339171 35699279 36149462 37069508SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 9, 9:49 AM CDT | Mesoscale Discussion | SPC | Hempstead, Howard, Lafayette, Little River, Miller, Pike and 1 more | 116 min |
| Apr 9, 12:07 PM CDT | Severe Thunderstorm Watch | SPC | Arkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 20 more | 6 hr |
| Apr 9, 1:25 PM CDT | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Chicot, Desha, Drew and 5 more | 95 min |
| Apr 9, 3:10 PM CDT | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Chicot, Cleveland, Desha and 5 more | 95 min |
| Apr 9, 3:13 PM CDT | Severe Thunderstorm Watch | SPC | Baxter, Fulton, Izard, Lawrence, Marion, Randolph and 1 more | 7 hr |
| Apr 9, 3:14 PM CDT | Mesoscale Discussion | SPC | Benton, Crawford, Franklin, Polk, Scott, Sebastian and 2 more | 61 min |
| Apr 9, 3:42 PM CDT | Severe Thunderstorm Watch | SPC | Ashley, Chicot, Clay, Craighead, Crittenden, Cross and 6 more | 7 hr |
| Apr 9, 5:19 PM CDT | Mesoscale Discussion | SPC | Ashley | 116 min |
| Apr 9, 5:32 PM CDT | Severe Thunderstorm Watch | SPC | Columbia, Union | 7 hr |
| Apr 9, 6:34 PM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Crawford, Madison, Washington | 116 min |
| Apr 9, 4:56 PM CDT | Mesoscale Discussion | SPC | Bollinger, Cape Girardeau, Carter, Madison, Perry, Sainte Genevieve and 4 more | 64 min |
| Apr 9, 3:55 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Atoka, Bryan, Caddo, Canadian, Carter and 48 more | 7 hr |
Nearby
Mesoscale Discussions in Arkansas, 2021Mesoscale Discussions in Missouri, 2021Mesoscale Discussions in Oklahoma, 2021Every mesoscale discussion in 2021
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.