Mesoscale Discussion 988

Issued

Jun 17, 2021, 11:36 AM CDT (16:36 UTC)

Expired

Jun 17, 2021, 1:30 PM CDT

In force

114 min

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch unlikely

Chance of a watch

20%

The Little Rock radar (KLZK), 78 km from the middle of the area, began a volume at 16:37 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.

819 
ACUS11 KWNS 171637
SWOMCD
SPC MCD 171636 
ARZ000-MOZ000-171830-

Mesoscale Discussion 0988
NWS Storm Prediction Center Norman OK
1136 AM CDT Thu Jun 17 2021

Areas affected...southern Missouri through northern and western
Arkansas

Concerning...Severe potential...Watch unlikely 

Valid 171636Z - 171830Z

Probability of Watch Issuance...20 percent

SUMMARY...Thunderstorms are expected to increase in coverage from
southern Missouri through northern and western Arkansas this
afternoon. The stronger storms will become capable of producing a
few instances of strong to severe wind gusts and marginally severe
hail.

DISCUSSION...As of late morning the atmosphere continues to
destabilize across western through northern AR into southern MO
supported by strong diabatic warming of the moist boundary layer.
Temperatures rising through the upper 80s F along with low 70s
dewpoints are promoting 2500-3000 J/kg MLCAPE. A weak surface
boundary was also indicated from southeast OK through western and
northern AR into southeast MO where boundary layer cumulus is
increasing, and an isolated storm has already developed over
southeast MO. As surface temperatures approach 90F, very little
convective inhibition should remain and storms are expected to
increase in coverage during the afternoon. An MCV was also indicated
across southwest MO moving generally south, and this feature might
have some influence on storm coverage. Storms will move generally
southwesterly under the influence of modest north northeasterly
winds aloft. Multicells / pulse storms should be the dominant modes
with some activity possibly evolving into small clusters. This
environment should support a few instances of hail and locally
strong to damaging gusts during the afternoon.

..Dial/Grams.. 06/17/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...PAH...MEG...LZK...SGF...SHV...TSA...

LAT...LON   34149437 35259421 36769318 36979077 35979075 35019207
            33769393 34149437

Mesoscale Discussions in Arkansas, 2021Mesoscale Discussions in Missouri, 2021Every mesoscale discussion in 2021

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.