Alert archive / South Dakota / Mesoscale Discussions in 2021

Mesoscale Discussion 919

June 11, 202112 counties in Minnesota; 14 counties in North Dakota; 27 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jun 11, 2021, 4:37 AM CDT for 12 counties in Minnesota; 14 counties in North Dakota; 27 counties in South Dakota. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued
Jun 11, 2021, 4:37 AM CDT (09:37 UTC)
Expired
Jun 11, 2021, 6:00 AM CDT
In force
83 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 255...256
All 53 counties

Big Stone County, MN, Clay County, MN, Grant County, MN, Kittson County, MN, Lac qui Parle County, MN, Marshall County, MN, Norman County, MN, Pennington County, MN, Polk County, MN, Red Lake County, MN, Traverse County, MN, Wilkin County, MN, Barnes County, ND, Cass County, ND, Cavalier County, ND, Grand Forks County, ND, Griggs County, ND, Nelson County, ND, Pembina County, ND, Ramsey County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Steele County, ND, Traill County, ND, Walsh County, ND, Aurora County, SD, Beadle County, SD, Brookings County, SD, Brown County, SD, Charles Mix County, SD, Clark County, SD, Codington County, SD, Davison County, SD, Day County, SD, Deuel County, SD, Douglas County, SD, Grant County, SD, Hamlin County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Marshall County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Roberts County, SD, Sanborn County, SD, Spink County, SD, Turner County, SD

The radar

The Aberdeen radar (KABR), 107 km from the middle of the area, began a volume at 09:38 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, 9.6 hours before the alert went out and 164 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 2021-06-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1337 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 2021-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
1337 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
2725 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
91 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted.

864 
ACUS11 KWNS 110937
SWOMCD
SPC MCD 110937 
MNZ000-SDZ000-NDZ000-111100-

Mesoscale Discussion 0919
NWS Storm Prediction Center Norman OK
0437 AM CDT Fri Jun 11 2021

Areas affected...eastern North Dakota/South Dakota and western
Minnesota

Concerning...Severe Thunderstorm Watch 255...256...

Valid 110937Z - 111100Z

The severe weather threat for Severe Thunderstorm Watch 255, 256
continues.

SUMMARY...Severe thunderstorms capable of damaging gusts will
continue the next couple of hours across the eastern Dakotas into
portions of western Minnesota.

DISCUSSION...A severe QLCS will continue to track eastward across
the eastern Dakotas at around 40-50 kt early this morning. Several
severe wind gusts around 60-80 mph have been measured over the past
hour or so with this line. Recent VWP data from ABR, where the line
recently passed, indicated a rear inflow jet around 60-70 kt around
2 km. While the QLCS is currently exiting the axis of greatest
instability, this strong rear inflow jet, and a southerly low level
jet around 30-40 kts ahead of the line will help to maintain strong
to severe storms for another couple hours as convection approaches
western MN. The current expectation is that convection should
gradually diminish in intensity with eastward extent as instability
and shear weak across western MN. While new downstream severe
thunderstorm watches are not anticipated at this time, local watch
extensions may be needed for parts of the Grand Forks and/or
Aberdeen CWAs depending on convective trends over the next hour or
so.

..Leitman.. 06/11/2021

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

ATTN...WFO...MPX...FGF...FSD...ABR...BIS...

LAT...LON   49079697 48079591 46469578 44049639 43029745 42969828
            43289877 43979887 46259841 47959887 48759928 49109909
            49079697

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 11, 1:58 AM CDTSevere Thunderstorm WatchSPCClay, Norman, Polk, Wilkin5 hr
Jun 11, 2:15 AM CDTSevere Thunderstorm WatchSPCBig Stone, Traverse5 hr
Jun 11, 9:35 AM CDTMesoscale DiscussionSPCBlue Earth, Dodge, Faribault, Fillmore, Freeborn, Le Sueur and 8 more115 min
Jun 11, 11:34 AM CDTMesoscale DiscussionSPCDakota, Dodge, Fillmore, Goodhue, Houston, Olmsted and 3 more116 min
Jun 10, 8:30 PM CDTMesoscale DiscussionSPCBillings, Burke, Divide, Golden Valley, McKenzie, Mountrail and 1 more2 hr
Jun 10, 9:54 PM CDTSevere Thunderstorm WatchSPCAdams, Billings, Bottineau, Bowman, Burke, Burleigh and 24 more5 hr
Jun 10, 11:07 PM CDTMesoscale DiscussionSPCAdams, Bowman, Grant, Hettinger, Slope, Stark83 min
Jun 10, 11:21 PM CDTMesoscale DiscussionSPCBottineau, Burke, Divide, McHenry, McKenzie, Mountrail and 3 more114 min
Jun 11, 12:52 AM CDTMesoscale DiscussionSPCBarnes, Benson, Cass, Cavalier, Dickey, Eddy and 17 more53 min
Jun 10, 8:28 PM CDTMesoscale DiscussionSPCBennett, Butte, Corson, Custer, Dewey, Fall River and 17 more92 min
Jun 10, 9:08 PM CDTSevere Thunderstorm WatchSPCBennett, Butte, Campbell, Corson, Custer, Dewey and 20 more6 hr
Jun 10, 11:50 PM CDTMesoscale DiscussionSPCDewey, Haakon, Jackson, Jones, Meade, Mellette and 5 more85 min

Nearby

Mesoscale Discussions in South Dakota, 2021Mesoscale Discussions in North Dakota, 2021Mesoscale Discussions in Minnesota, 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.