Alert archive / Missouri / Mesoscale Discussions in 2021

Mesoscale Discussion 1893

October 24, 202147 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Oct 24, 2021, 5:25 PM CDT for 47 counties in Missouri. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Oct 24, 2021, 5:25 PM CDT (22:25 UTC)
Expired
Oct 24, 2021, 7:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Tornado watch 531
All 47 counties

Adair County, MO, Audrain County, MO, Benton County, MO, Boone County, MO, Callaway County, MO, Camden County, MO, Cedar County, MO, Chariton County, MO, Cole County, MO, Cooper County, MO, Crawford County, MO, Dade County, MO, Dallas County, MO, Dent County, MO, Franklin County, MO, Gasconade County, MO, Greene County, MO, Hickory County, MO, Howard County, MO, Knox County, MO, Laclede County, MO, Lewis County, MO, Lincoln County, MO, Linn County, MO, Macon County, MO, Maries County, MO, Marion County, MO, Miller County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Morgan County, MO, Osage County, MO, Pettis County, MO, Phelps County, MO, Pike County, MO, Polk County, MO, Pulaski County, MO, Ralls County, MO, Randolph County, MO, Saline County, MO, Shelby County, MO, Sullivan County, MO, Texas County, MO, Warren County, MO, Webster County, MO, Wright County, MO

The radar

The St Louis radar (KLSX), 139 km from the middle of the area, began a volume at 22:24 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 12:00Z, 10.4 hours before the alert went out and 226 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 12:00Z on 2021-10-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 860 joules per kilogram.LCLLFCEL10008507005003002001001 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 12:00Z on 2021-10-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 225 square meters per square second.19395878Sfc1 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
860 J/kg
Mixed-layer CIN
-152 J/kg
Mixed-layer LCL
737 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
225 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

635 
ACUS11 KWNS 242225
SWOMCD
SPC MCD 242225 
MOZ000-ILZ000-250030-

Mesoscale Discussion 1893
NWS Storm Prediction Center Norman OK
0525 PM CDT Sun Oct 24 2021

Areas affected...portions of western into central Missouri

Concerning...Tornado Watch 531...

Valid 242225Z - 250030Z

The severe weather threat for Tornado Watch 531 continues.

SUMMARY...The threat for severe storms, including tornadoes,
continues across Tornado Watch 0531 in central MO, and is expected
to persist through the remainder of the evening. The greatest short
term threat is associated with storms immediately ahead of the cold
front and in proximity to the warm front, though the severe threat
may increase further south with time.

DISCUSSION...Multiple sustained semi-discrete supercell structures
are in progress across portions of north-central into central MO
immediately ahead of a cold front and within proximity to a diffuse
warm front. In addition, storms are also attempting to mature
further south along the cold front into southwest MO, as well as
with a second confluence zone east of SGF. Tornadoes have been
reported over the past few hours across northern/central MO with
storms closer to the warm front, where latest METAR observations
depict more backed surface flow. These storms have the greatest
threat of continued tornado potential in the short term. 

The low-level jet is expected to intensify going into the evening
hours across portions of central into eastern MO. 2154Z SGF VWP
showed over 200 m2/s2 SRH, and these values are expected to
gradually increase this evening. As such, a tornado threat may
develop with any sustained supercell structures that manage to
develop in southern MO. In addition, severe hail and damaging
rear-flank downdraft winds may also accompany any mature supercells
as well.

..Squitieri/Hart.. 10/24/2021

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

ATTN...WFO...LSX...DVN...SGF...EAX...

LAT...LON   37229123 37009191 36959239 37079369 37299445 37989380
            38819329 39769332 40229324 40349240 40219189 40039150
            39729130 39009083 38469093 37809119 37229123

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 23, 9:14 PM CDTMesoscale DiscussionSPCAdair, Andrew, Atchison, Buchanan, Caldwell, Carroll and 26 more3 hr
Oct 23, 9:53 PM CDTSevere Thunderstorm WatchSPCAdair, Andrew, Atchison, Buchanan, Caldwell, Carroll and 24 more7 hr
Oct 24, 2:13 AM CDTMesoscale DiscussionSPCAndrew, Audrain, Boone, Buchanan, Caldwell, Callaway and 24 more2 hr
Oct 24, 12:40 PM CDTMesoscale DiscussionSPCAudrain, Barry, Barton, Benton, Boone, Callaway and 60 more3 hr
Oct 24, 2:06 PM CDTTornado WatchSPCAdair, Andrew, Audrain, Barry, Barton, Bates and 83 more9 hr
Oct 24, 3:28 PM CDTMesoscale DiscussionSPCBates, Caldwell, Carroll, Cass, Daviess, Grundy and 10 more92 min
Oct 24, 3:50 PM CDTMesoscale DiscussionSPCAudrain, Callaway, Cole, Franklin, Gasconade, Lincoln and 8 more85 min
Oct 24, 5:11 PM CDTMesoscale DiscussionSPCSaint Louis, City of Saint Louis3 hr
Oct 24, 5:44 PM CDTTornado WatchSPCBollinger, Butler, Cape Girardeau, Carter, Madison, Mississippi and 8 more7 hr

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.