Mesoscale Discussion 1796

Issued

Oct 2, 2021, 1:50 PM CDT (18:50 UTC)

Expired

Oct 2, 2021, 4:15 PM CDT

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch unlikely

Chance of a watch

5%

The Springfield radar (KSGF), 97 km from the middle of the area, began a volume at 18:50 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.

310 
ACUS11 KWNS 021851
SWOMCD
SPC MCD 021850 
MOZ000-ARZ000-022115-

Mesoscale Discussion 1796
NWS Storm Prediction Center Norman OK
0150 PM CDT Sat Oct 02 2021

Areas affected...Portions of western/central AR and southern MO

Concerning...Severe potential...Watch unlikely 

Valid 021850Z - 022115Z

Probability of Watch Issuance...5 percent

SUMMARY...An isolated severe threat, with both gusty winds and hail
possible, should continue through the rest of the afternoon. Watch
issuance is not expected.

DISCUSSION...Storms have gradually increased in coverage across
parts of southwestern MO and western AR early this afternoon. This
activity is occurring on the southern flank on a MCV over western
MO, and is being aided by modest lift associated with a
low-amplitude shortwave trough moving slowly eastward from the
southern/central Plains across the Ozarks. Filtered diurnal heating
of a moist low-level airmass across much of AR/MO has allowed for
weak instability to develop, with up to 1000 J/kg of MLCAPE present
per mesoanalysis estimates. Although low-level flow remains rather
modest, some strengthening of southwesterly winds is present at mid
levels owing to the presence of the shortwave trough. Around 30-35
kt of flow has been estimated above 5 km AGL by recent VWPs from
KSRX and KSGF. Similar values of deep-layer shear may prove
sufficient for updraft organization, with multicells probably
becoming the dominant storm mode with time this afternoon.
Occasional strong to damaging winds may occur with the strongest
cells as they move east-northeastward. Cool mid-level temperatures
may also aid marginally severe hail with any supercell that can
develop, but the lack of stronger deep-layer shear suggests the
supercell threat will likely be short lived. The overall severe
threat should remain rather isolated/marginal this afternoon, and
watch issuance is not expected at this time.

..Gleason/Guyer.. 10/02/2021

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

ATTN...WFO...LZK...SGF...TSA...

LAT...LON   35599444 36249384 36569336 37009330 37599342 37909325
            38199245 38069179 37389131 36639138 35519183 35039278
            34869362 34889438 35279440 35599444

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.