Alert archive / Missouri / Mesoscale Discussions in 2021

Mesoscale Discussion 2039

December 15, 20215 states

The Storm Prediction Center issued this mesoscale discussion at Dec 15, 2021, 9:48 PM CST for 5 states. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued
Dec 15, 2021, 9:48 PM CST (03:48 UTC)
Expired
Dec 15, 2021, 11:15 PM CST
In force
87 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 566
All 71 counties

Benton County, AR, Carroll County, AR, Adams County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Jersey County, IL, Knox County, IL, Logan County, IL, Mason County, IL, McDonough County, IL, Menard County, IL, Morgan County, IL, Peoria County, IL, Pike County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Warren County, IL, Cherokee County, KS, Audrain County, MO, Barry County, MO, Barton County, MO, Callaway County, MO, Camden County, MO, Cedar County, MO, Christian County, MO, Cole County, MO, Crawford County, MO, Dade County, MO, Dallas County, MO, Douglas County, MO, Franklin County, MO, Gasconade County, MO, Greene County, MO, Hickory County, MO, Jasper County, MO, Laclede County, MO, Lawrence County, MO, Lincoln County, MO, Maries County, MO, Marion County, MO, McDonald County, MO, Miller County, MO, Moniteau County, MO, Montgomery County, MO, Morgan County, MO, Newton County, MO, Osage County, MO, Phelps County, MO, Pike County, MO, Polk County, MO, Pulaski County, MO, Ralls County, MO, Saint Charles County, MO, Stone County, MO, Taney County, MO, Warren County, MO, Webster County, MO, Wright County, MO, Craig County, OK, Delaware County, OK, Mayes County, OK, Ottawa County, OK, Rogers County, OK, Tulsa County, OK

The radar

The St Louis radar (KLSX), 153 km from the middle of the area, began a volume at 03:51 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, 3.8 hours before the alert went out and 207 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 2021-12-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 9 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 00:00Z on 2021-12-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 310 square meters per square second.1939587897Sfc1 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
9 J/kg
Mixed-layer CIN
-387 J/kg
Mixed-layer LCL
1246 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
310 m²/s²
0-3 km storm-relative helicity
677 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

822 
ACUS11 KWNS 160348
SWOMCD
SPC MCD 160348 
ILZ000-MOZ000-IAZ000-ARZ000-OKZ000-KSZ000-160515-

Mesoscale Discussion 2039
NWS Storm Prediction Center Norman OK
0948 PM CST Wed Dec 15 2021

Areas affected...portions of far western Illinois...northeast to
southwest Missouri...far northeastern Oklahoma

Concerning...Severe Thunderstorm Watch 566...

Valid 160348Z - 160515Z

The severe weather threat for Severe Thunderstorm Watch 566
continues.

SUMMARY...A few damaging/severe gusts remain possible for a few more
hours with a squall line. Damaging gusts will be more likely across
east-central Missouri into western IL, where synoptic forcing is
greater. A local WW extension may be needed in parts of central IL.

DISCUSSION...A broken squall line continues to produce occasional
damaging or severe gusts despite a gradual decline in intensity
noted over the past couple of hours. Buoyancy is on the wane across
portions of the Mid Mississippi Valley, with synoptic-scale upper
support drifting northeast with the surface low into the Upper
Mississippi Valley. However, intense low-level winds (70+ kt at 1 km
AGL) prevail ahead of the squall line, so any downward momentum
transport in the stronger convective cores can easily support severe
gusts. The severe threat is expected to persist for a few more
hours, especially across eastern MO into central IL, where
relatively stronger forcing for ascent is present. As such, local WW
extension may be needed in parts of central IL should the line hold
together.

..Squitieri/Hart.. 12/16/2021

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

ATTN...WFO...ILX...LSX...DVN...LZK...SGF...EAX...TSA...ICT...

LAT...LON   36239662 37119497 38929224 40859105 41249055 41088980
            40818932 40348911 39438976 38249098 37169217 36259337
            36119405 36019538 36239662

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 15, 6:00 PM CSTSevere Thunderstorm WatchSPCBenton6 hr
Dec 16, 2:08 PM CSTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 29 more3 hr
Dec 15, 9:44 PM CSTSevere Thunderstorm WatchSPCBoone, Lee, Ogle, Winnebago3 hr
Dec 15, 7:14 PM CSTMesoscale DiscussionSPCBourbon, Cherokee, Crawford, Labette, Linn, Montgomery and 1 more91 min

Nearby

Mesoscale Discussions in Missouri, 2021Mesoscale Discussions in Illinois, 2021Mesoscale Discussions in Oklahoma, 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.