Alert archive / Arkansas / Mesoscale Discussions in 2021
Mesoscale Discussion 768
The Storm Prediction Center issued this mesoscale discussion at May 27, 2021, 2:06 PM CDT for 29 counties in Arkansas; 4 counties in Missouri. It was in force for 84 min.
The area
The outline as issued.
The facts
- Issued
- May 27, 2021, 2:06 PM CDT (19:06 UTC)
- Expired
- May 27, 2021, 3:30 PM CDT
- In force
- 84 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 40%
All 33 counties
Baxter County, AR, Boone County, AR, Clay County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Johnson County, AR, Lawrence County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Newton County, AR, Perry County, AR, Pope County, AR, Randolph County, AR, Scott County, AR, Searcy County, AR, Sharp County, AR, Stone County, AR, Van Buren County, AR, White County, AR, Yell County, AR, Butler County, MO, Dunklin County, MO, Oregon County, MO, Ripley County, MO
The radar
The Little Rock radar (KLZK), 107 km from the middle of the area, began a volume at 19:08 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, 7.1 hours before the alert went out and 165 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
- 295 J/kg
- Mixed-layer CIN
- -229 J/kg
- Mixed-layer LCL
- 964 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 69 m²/s²
- 0-3 km storm-relative helicity
- 160 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
The text
As transmitted.
271
ACUS11 KWNS 271907
SWOMCD
SPC MCD 271906
ARZ000-MOZ000-272030-
Mesoscale Discussion 0768
NWS Storm Prediction Center Norman OK
0206 PM CDT Thu May 27 2021
Areas affected...the northern Arkansas vicinity
Concerning...Severe potential...Watch possible
Valid 271906Z - 272030Z
Probability of Watch Issuance...40 percent
SUMMARY...Storms developing/spreading into northern Arkansas over
the next 1 to 2 hours may require WW issuance.
DISCUSSION...Latest visible satellite imagery shows that broken
cloud cover persisting across northern Arkansas south of the
southwestern Missouri convection, which has allowed diurnal heating
to push mixed-layer CAPE values into the 200 to 2500 J/kg range
across this area. Cumulus continues to slowly grow vertically
across portions of northern Arkansas, with some towering cu/small
CBs indicated over northwestern Arkansas.
Expect storms to evolve across this area over the next 1 to 2 hours,
initially over the northwest where visible imagery indicates outflow
now moving southward into Benton and Carroll counties. Given
continued destabilization, and shear sufficient for multicell
organization and possible/weak mid-level rotation, evolving risk for
marginal hail and gusty/locally damaging winds may be sufficient to
warrant WW issuance.
..Goss/Hart.. 05/27/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...MEG...LZK...SGF...TSA...
LAT...LON 35679412 36409346 37019007 35948997 34799235 34819424
35679412SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 27, 11:04 AM CDT | Mesoscale Discussion | SPC | Baxter, Benton, Boone, Carroll, Cleburne, Crawford and 15 more | 86 min |
| May 27, 11:29 AM CDT | Mesoscale Discussion | SPC | Crawford | 61 min |
| May 27, 4:52 PM CDT | Mesoscale Discussion | SPC | Arkansas, Baxter, Benton, Boone, Carroll, Clark and 47 more | 83 min |
| May 27, 5:12 PM CDT | Severe Thunderstorm Watch | SPC | Arkansas, Baxter, Benton, Boone, Carroll, Clark and 41 more | 8 hr |
| May 27, 5:21 PM CDT | Mesoscale Discussion | SPC | Clay, Craighead, Greene, Mississippi | 114 min |
| May 27, 12:51 AM CDT | Mesoscale Discussion | SPC | Barton, Buchanan, Platte | 84 min |
| May 27, 1:05 AM CDT | Severe Thunderstorm Watch | SPC | Bates, Buchanan, Cass, Clay, Jackson, Platte and 1 more | 7 hr |
| May 27, 5:28 AM CDT | Mesoscale Discussion | SPC | Cass, Jackson | 92 min |
| May 27, 11:26 AM CDT | Severe Thunderstorm Watch | SPC | Barry, Barton, Bollinger, Camden, Cape Girardeau, Carter and 45 more | 8 hr |
| May 27, 12:57 PM CDT | Mesoscale Discussion | SPC | Barry, Christian, Crawford, Dallas, Dent, Franklin and 14 more | 93 min |
| May 27, 1:36 PM CDT | Mesoscale Discussion | SPC | Andrew, Buchanan, Cass, Clay, Clinton, DeKalb and 2 more | 54 min |
| May 27, 2:20 PM CDT | Mesoscale Discussion | SPC | Barry, Bollinger, Butler, Cape Girardeau, Carter, Christian and 27 more | 85 min |
| May 27, 3:38 PM CDT | Mesoscale Discussion | SPC | Bollinger, Cape Girardeau, Carter, Madison, Oregon, Perry and 3 more | 67 min |
| May 27, 6:03 PM CDT | Mesoscale Discussion | SPC | Adair, Audrain, Boone, Buchanan, Caldwell, Carroll and 27 more | 87 min |
Nearby
Mesoscale Discussions in Arkansas, 2021Mesoscale Discussions in Missouri, 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.