Mesoscale Discussion 1407

Issued

Jul 31, 2021, 5:09 PM CDT (22:09 UTC)

Expired

Jul 31, 2021, 7:15 PM CDT

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch possible

Chance of a watch

40%

The Springfield radar (KSGF), 135 km from the middle of the area, began a volume at 22:08 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.

002 
ACUS11 KWNS 312209
SWOMCD
SPC MCD 312209 
MOZ000-ARZ000-KSZ000-010015-

Mesoscale Discussion 1407
NWS Storm Prediction Center Norman OK
0509 PM CDT Sat Jul 31 2021

Areas affected...South to southeast Missouri

Concerning...Severe potential...Watch possible 

Valid 312209Z - 010015Z

Probability of Watch Issuance...40 percent

SUMMARY...Strong to severe thunderstorms developing along a cold
front may gradually grow upscale and pose a damaging wind threat
this evening. Trends will be monitored, and a watch may be needed if
robust upscale growth occurs.

DISCUSSION...Latest surface observations and regional radar mosaics
show strong to severe thunderstorms developing along a cold front
that is gradually sagging southward into south-central MO. The
thermodynamic environment ahead of these storms is supportive for
continued growth with nearly 3500 J/kg MLCAPE noted in recent
mesoanalysis estimates. This warm sector is bound to the east by the
residual cool outflow from prior convection over the MO/TN/KY/IL
border where an MLCIN maxima is noted. With only a few more hours of
insolation, destabilization of the remnant cold pool over the mid MS
river valley is uncertain and may confine the severe threat. Storm
motions to the east/southeast along the front and outflow boundary
will likely favor loose clustering and gradual upscale growth this
evening. Stronger flow on the eastern periphery of the warm sector
is supporting 30-40 knots of effective bulk shear, which will aid in
some storm organization. While severe hail is possible with
initially discrete cells, damaging winds appear more probable
heading into the mid/late evening hours. Trends will continue to be
monitored, and a watch is possible later this evening if robust
upscale growth occurs over south/southeast MO and into the mid-MS
river valley region.

..Moore/Goss.. 07/31/2021

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

ATTN...WFO...PAH...MEG...LSX...LZK...SGF...EAX...

LAT...LON   38049099 37749025 37328973 36668959 36218972 36069008
            36209070 36439178 36599280 36819385 37079440 37569463
            38249457 38359409 38049099

Mesoscale Discussions in Missouri, 2021Mesoscale Discussions in Arkansas, 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.