Alert archive / South Dakota / Mesoscale Discussions in 2021

Mesoscale Discussion 1210

July 9, 20214 states

The Storm Prediction Center issued this mesoscale discussion at Jul 9, 2021, 2:41 AM CDT for 4 states. It was in force for 34 min.

The area

The outline as issued.

The facts

Issued
Jul 9, 2021, 2:41 AM CDT (07:41 UTC)
Expired
Jul 9, 2021, 3:15 AM CDT
In force
34 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 355
All 49 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Crawford County, IA, Ida County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sac County, IA, Sioux County, IA, Woodbury County, IA, Rock County, MN, Cedar County, NE, Dakota County, NE, Dixon County, NE, Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brule County, SD, Buffalo County, SD, Charles Mix County, SD, Clay County, SD, Corson County, SD, Davison County, SD, Dewey County, SD, Douglas County, SD, Faulk County, SD, Hand County, SD, Hanson County, SD, Hughes County, SD, Hutchinson County, SD, Hyde County, SD, Jerauld County, SD, Jones County, SD, Lake County, SD, Lincoln County, SD, Lyman County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Potter County, SD, Sanborn County, SD, Stanley County, SD, Sully County, SD, Turner County, SD, Union County, SD, Walworth County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 167 km from the middle of the area, began a volume at 07:45 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

Aberdeen, SD (KABR), launched 00:00Z, 7.7 hours before the alert went out and 113 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, Aberdeen, SD at 00:00Z on 2021-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 82 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, Aberdeen, SD at 00:00Z on 2021-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 133 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
82 J/kg
Mixed-layer CIN
-125 J/kg
Mixed-layer LCL
996 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
211 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

488 
ACUS11 KWNS 090742
SWOMCD
SPC MCD 090741 
IAZ000-MNZ000-NEZ000-SDZ000-090815-

Mesoscale Discussion 1210
NWS Storm Prediction Center Norman OK
0241 AM CDT Fri Jul 09 2021

Areas affected...portions of South Dakota southeastward parts of
western Iowa

Concerning...Severe Thunderstorm Watch 355...

Valid 090741Z - 090815Z

The severe weather threat for Severe Thunderstorm Watch 355
continues.

SUMMARY...Local risk for hail may continue for a few more hours, but
new WW issuance is not expected for ongoing convection.

DISCUSSION...Storms continue across portions of the north-central
U.S. at this time, including across parts of WW 355.  However,
storms are highly elevated, with risk expected to remain limited to
hail near or less than 1" in diameter the remainder of the overnight
hours.  As such, new WW issuance is not anticipated beyond
expiration of the existing watch.

..Goss.. 07/09/2021

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

ATTN...WFO...DMX...FSD...OAX...ABR...UNR...

LAT...LON   45850191 45730046 43179502 41929514 42289696 42759766
            43790103 45850191

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 8, 9:33 PM CDTSevere Thunderstorm WatchSPCBuena Vista, Cherokee, Clay, Ida, Lyon, O'Brien and 3 more5 hr
Jul 9, 1:28 PM CDTMesoscale DiscussionSPCBoone, Dallas, Lucas, Polk, Warren2 hr
Jul 9, 5:40 PM CDTMesoscale DiscussionSPCBenton, Black Hawk, Bremer, Buchanan, Butler, Cedar and 15 more95 min
Jul 9, 2:38 PM CDTMesoscale DiscussionSPCArthur, Banner, Box Butte, Chase, Cheyenne, Deuel and 16 more97 min
Jul 9, 3:16 PM CDTSevere Thunderstorm WatchSPCArthur, Banner, Blaine, Box Butte, Brown, Chase and 30 more9 hr
Jul 9, 6:16 PM CDTMesoscale DiscussionSPCArthur, Banner, Blaine, Box Butte, Brown, Buffalo and 35 more119 min
Jul 8, 7:08 PM CDTMesoscale DiscussionSPCBennett, Haakon, Jackson, Meade, Oglala Lakota, Pennington and 2 more97 min
Jul 8, 8:54 PM CDTMesoscale DiscussionSPCAurora, Beadle, Brule, Buffalo, Campbell, Corson and 16 more2 hr
Jul 9, 6:33 PM CDTSevere Thunderstorm WatchSPCCuster, Fall River, Lawrence, Oglala Lakota, Pennington4 hr

Nearby

Mesoscale Discussions in South Dakota, 2021Mesoscale Discussions in Iowa, 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.