Alert archive / Missouri / Mesoscale Discussions in 2021

Mesoscale Discussion 1448

August 8, 20215 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Aug 8, 2021, 7:14 PM CDT for 5 counties in Missouri. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Aug 8, 2021, 7:14 PM CDT (00:14 UTC)
Expired
Aug 8, 2021, 8:45 PM CDT
In force
91 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 415

Counties Butler County, MO, Carter County, MO, Shannon County, MO, Texas County, MO, Wayne County, MO

The radar

The Springfield radar (KSGF), 180 km from the middle of the area, began a volume at 00:14 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 nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 0.2 hours before the alert went out and 216 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.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 00:00Z on 2021-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2779 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 00:00Z on 2021-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
2779 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
1238 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
193 m²/s²
Significant tornado parameter
0.0
Supercell composite
8.1

Open this sounding in Storm Lab

The text

As transmitted.

481 
ACUS11 KWNS 090015
SWOMCD
SPC MCD 090014 
MOZ000-090145-

Mesoscale Discussion 1448
NWS Storm Prediction Center Norman OK
0714 PM CDT Sun Aug 08 2021

Areas affected...Parts of southern Missouri

Concerning...Severe Thunderstorm Watch 415...

Valid 090014Z - 090145Z

The severe weather threat for Severe Thunderstorm Watch 415
continues.

SUMMARY...A small evolving cluster of storms may continue to develop
through 9-11 PM CDT, and pose at least some risk for potentially
damaging wind gusts in a corridor near/north of West Plains through
Poplar Bluff.  It is not certain that a new severe weather watch
will be needed, but trends will continue to be monitored for this
possibility.

DISCUSSION...There has been a gradual consolidation of renewed
convective development, including some recent intensification of
storm, near or just north of the southern flank of conglomerate
convective outflow which trails a modest convective system spreading
across middle Mississippi Valley.  The surface boundary extends from
near Springfield east-southeastward to the north of West Plains and
Poplar Bluff, with warm advection across the boundary, and inflow of
seasonably moist air characterized by CAPE in excess of 2000 J/kg,
supporting convective development.  

Although westerly mid-level flow along the boundary appears a
relatively modest 20-30 kt, it is possible that vertical shear may
be sufficient to support further organization of the evolving
cluster, particularly with some strengthening of south-southwesterly
flow just above the boundary layer after dark.  It is possible that
this could gradually be accompanied by increasing potential for
strong surface gusts as the more vigorous convection propagates
along the boundary through mid to late evening.  However, the extent
of this potential remains unclear, and it might remain isolated
and/or marginal enough that a new severe weather watch will not be
need.

..Kerr.. 08/09/2021

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

ATTN...WFO...PAH...LSX...SGF...

LAT...LON   37399228 37369104 36989001 36649034 36869126 36929245
            37399228

Nearby

Mesoscale 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.