Alert archive / North Dakota / Mesoscale Discussions in 2021

Mesoscale Discussion 871

June 7, 20218 counties in North Dakota; 7 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jun 7, 2021, 5:08 PM CDT for 8 counties in North Dakota; 7 counties in South Dakota. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
Jun 7, 2021, 5:08 PM CDT (22:08 UTC)
Expired
Jun 7, 2021, 6:45 PM CDT
In force
97 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
60%

Counties Barnes County, ND, Dickey County, ND, Emmons County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Sargent County, ND, Stutsman County, ND, Brown County, SD, Campbell County, SD, Edmunds County, SD, Faulk County, SD, McPherson County, SD, Potter County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 111 km from the middle of the area, began a volume at 22:07 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

Bismarck Municip, ND (KBIS), launched 12:00Z, 10.1 hours before the alert went out and 122 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, Bismarck Municip, ND at 12:00Z on 2021-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Bismarck Municip, ND at 12:00Z on 2021-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 127 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2578 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
598 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted.

575 
ACUS11 KWNS 072208
SWOMCD
SPC MCD 072208 
SDZ000-NDZ000-072345-

Mesoscale Discussion 0871
NWS Storm Prediction Center Norman OK
0508 PM CDT Mon Jun 07 2021

Areas affected...Dakotas

Concerning...Severe potential...Watch possible 

Valid 072208Z - 072345Z

Probability of Watch Issuance...60 percent

SUMMARY...Thunderstorm potential is increasing across portions of
the Dakotas. Large hail and damaging wind threat may warrant a
severe thunderstorm watch in the next 1-2 hours.

DISCUSSION...Surface temperatures have soared to near 100F across
central/north-central SD this afternoon. These readings are at/above
forecast convective temperatures and recent visible satellite
imagery supports this with deepening cu field and clustering
occurring over southeast Corson County/northeast Dewey County, just
west of Mobridge. This activity is evolving along the northeastern
plume of steepest low-level lapse rates and should continue to
mature over the next few hours. These trends are in line with
earlier thinking regarding the possibility for organized convection
evolving across this region, then spreading downstream toward
southeast ND. Forecast soundings suggest hail/wind are the primary
threats. WW may be warranted to account for this scenario.

..Darrow/Thompson.. 06/07/2021

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

ATTN...WFO...FGF...ABR...BIS...

LAT...LON   45820091 46780009 47419815 46139751 44839932 44810076
            45820091

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 7, 5:45 PM CDTSevere Thunderstorm WatchSPCBarnes, Cass, Dickey, Emmons, Foster, Grand Forks and 11 more8 hr
Jun 7, 3:49 PM CDTMesoscale DiscussionSPCBennett, Custer, Fall River, Haakon, Jackson, Meade and 2 more116 min

Nearby

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