Alert archive / Missouri / Mesoscale Discussions in 2021

Mesoscale Discussion 1084

June 24, 20214 states

The Storm Prediction Center issued this mesoscale discussion at Jun 24, 2021, 7:29 PM CDT for 4 states. It was in force for 61 min.

The area

The outline as issued.

The facts

Issued
Jun 24, 2021, 7:29 PM CDT (00:29 UTC)
Expired
Jun 24, 2021, 8:30 PM CDT
In force
61 min
Issued by
the Storm Prediction Center
Concerning
Tornado watch 309...310
All 27 counties

Fremont County, IA, Page County, IA, Ringgold County, IA, Taylor County, IA, Atchison County, KS, Brown County, KS, Doniphan County, KS, Jackson County, KS, Marshall County, KS, Nemaha County, KS, Pottawatomie County, KS, Riley County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, DeKalb County, MO, Gentry County, MO, Harrison County, MO, Holt County, MO, Mercer County, MO, Nodaway County, MO, Worth County, MO, Johnson County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE

The radar

The Topeka radar (KTWX), 154 km from the middle of the area, began a volume at 00:31 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Topeka, KS (KTOP), launched 00:00Z, 0.5 hours before the alert went out and 129 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, Topeka, KS at 00:00Z on 2021-06-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2766 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, Topeka, KS at 00:00Z on 2021-06-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 225 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
2766 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
1424 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
225 m²/s²
0-3 km storm-relative helicity
404 m²/s²
Significant tornado parameter
2.2
Supercell composite
23.2

Open this sounding in Storm Lab

The text

As transmitted.

218 
ACUS11 KWNS 250029
SWOMCD
SPC MCD 250029 
MOZ000-IAZ000-KSZ000-NEZ000-250130-

Mesoscale Discussion 1084
NWS Storm Prediction Center Norman OK
0729 PM CDT Thu Jun 24 2021

Areas affected...northeast Kansas and southeastern Nebraska into
northwestern Missouri and southwest Iowa.

Concerning...Tornado Watch 309...310...

Valid 250029Z - 250130Z

The severe weather threat for Tornado Watch 309, 310 continues.

SUMMARY...The threat for damaging wind gusts, large hail, and a
couple tornadoes remains early this evening. A transition to more of
a damaging wind threat appears likely over the next hour or two.

DISCUSSION...Evening radar observations showed several clusters of
thunderstorms ongoing near the Kansas, Nebraska, Missouri, and Iowa
state lines. A cluster of HP supercells have evolved across far
northeast Kansas and northwestern Missouri. Additional discrete
development has taken place over the last 20 minutes south, near
Topeka. These rotating storms may continue to pose a risk for
tornadoes over the next couple of hours given strong low-level shear
and plentiful instability.

A transition to a more linear storm mode was observed across
southeastern Nebraska and western Iowa, north of the primary
baroclinic zone. This cluster is likely the beginning of a stronger
MCS depicted by CAM guidance to move southeast across northern and
central Missouri later this evening. Additional storm
development/conglomeration appears likely near sunset ahead of the
increasing low-level jet. A tornado or two will remain possible with
the better organized line segments given strong low-level shear, but
a transition to a greater damaging wind threat will likely evolve as
cold pools strengthen and storms turn southeastward toward 01-03z.

..Lyons.. 06/25/2021

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

ATTN...WFO...DMX...EAX...OAX...TOP...

LAT...LON   39179702 39789671 40559655 40829579 40849501 40799417
            40679366 40449333 40349333 40209363 39699453 39509494
            39229587 39179702

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 24, 11:23 PM CDTMesoscale DiscussionSPCLee2 hr
Jun 24, 11:47 PM CDTTornado WatchSPCDes Moines, Henry, Lee4 hr
Jun 25, 1:00 PM CDTMesoscale DiscussionSPCBenton, Black Hawk, Boone, Buchanan, Buena Vista, Butler and 29 more2 hr
Jun 24, 8:13 PM CDTMesoscale DiscussionSPCBarton, Edwards, Ellis, Ellsworth, Finney, Ford and 29 more2 hr
Jun 24, 8:33 PM CDTMesoscale DiscussionSPCAtchison, Doniphan, Douglas, Franklin, Jefferson, Johnson and 3 more87 min
Jun 24, 8:57 PM CDTSevere Thunderstorm WatchSPCAtchison, Douglas, Franklin, Geary, Jackson, Jefferson and 9 more6 hr
Jun 24, 10:30 PM CDTMesoscale DiscussionSPCClark, Edwards, Ellis, Finney, Ford, Gove and 14 more60 min
Jun 25, 1:40 AM CDTMesoscale DiscussionSPCAllen, Anderson, Butler, Chase, Coffey, Dickinson and 16 more3 hr
Jun 25, 11:56 AM CDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Butler, Chase, Coffey and 17 more3 hr
Jun 25, 1:21 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Jewell, Norton, Phillips, Rawlins and 4 more114 min
Jun 25, 1:43 PM CDTSevere Thunderstorm WatchSPCAllen, Anderson, Bourbon, Butler, Chase, Coffey and 32 more9 hr
Jun 25, 2:11 PM CDTMesoscale DiscussionSPCClark, Finney, Ford, Gove, Grant, Gray and 18 more2 hr
Jun 25, 2:30 PM CDTSevere Thunderstorm WatchSPCBarber, Barton, Clark, Comanche, Edwards, Finney and 20 more10 hr
Jun 25, 3:07 PM CDTSevere Thunderstorm WatchSPCCheyenne, Decatur, Gove, Graham, Greeley, Jewell and 11 more6 hr
Jun 25, 3:13 PM CDTMesoscale DiscussionSPCAnderson, Chase, Coffey, Douglas, Franklin, Johnson and 6 more2 hr
Jun 25, 5:54 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Gove, Graham, Greeley, Jewell and 11 more66 min
Jun 25, 6:21 PM CDTMesoscale DiscussionSPCAllen, Bourbon, Butler, Greenwood, Harvey, Linn and 4 more84 min
Jun 25, 12:57 PM CDTMesoscale DiscussionSPCBollinger, Cape Girardeau, Madison, Perry2 hr
Jun 25, 4:46 PM CDTMesoscale DiscussionSPCAudrain, Boone, Callaway, Cole, Franklin, Gasconade and 14 more59 min
Jun 25, 5:06 PM CDTSevere Thunderstorm WatchSPCAudrain, Boone, Callaway, Camden, Cole, Crawford and 25 more6 hr

Nearby

Mesoscale Discussions in Missouri, 2021Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in Nebraska, 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.