Alert archive / South Dakota / Mesoscale Discussions in 2018

Mesoscale Discussion 990

July 2, 20184 states

The Storm Prediction Center issued this mesoscale discussion at Jul 2, 2018, 9:50 PM CDT for 4 states. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued: Jul 2, 2018, 9:50 PM CDT (02:50 UTC)
Expired: Jul 2, 2018, 11:45 PM CDT
In force: 115 min
Issued by: the Storm Prediction Center

All 44 counties

Traverse County, MN, Wilkin County, MN, Big Horn County, MT, Carter County, MT, Custer County, MT, Fallon County, MT, Powder River County, MT, Rosebud County, MT, Treasure County, MT, Yellowstone County, MT, Adams County, ND, Bowman County, ND, Dickey County, ND, Emmons County, ND, Grant County, ND, Hettinger County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Morton County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Sioux County, ND, Slope County, ND, Brown County, SD, Campbell County, SD, Clark County, SD, Codington County, SD, Corson County, SD, Day County, SD, Deuel County, SD, Edmunds County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Harding County, SD, Marshall County, SD, McPherson County, SD, Perkins County, SD, Roberts County, SD, Spink County, SD, Walworth County, SD

The radar

The Bismarck radar (KBIS), 142 km from the middle of the area, began a volume at 02:53 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

Bismarck Municip, ND (KBIS), launched 00:00Z, 2.8 hours before the alert went out and 143 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 86 J/kg
Mixed-layer CIN: -47 J/kg
Mixed-layer LCL: 2084 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 102 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 2, 7:36 PM CDT	Severe Thunderstorm Watch	SPC	Big Stone, Traverse, Wilkin	9 hr
Jul 2, 11:32 PM CDT	Mesoscale Discussion	SPC	Becker, Big Stone, Cass, Chippewa, Clay, Douglas and 14 more	88 min
Jul 3, 1:59 AM CDT	Severe Thunderstorm Watch	SPC	Big Stone, Clay, Norman, Traverse, Wilkin	7 hr
Jul 3, 4:15 AM CDT	Mesoscale Discussion	SPC	Big Stone, Clay, Norman, Traverse, Wilkin	90 min
Jul 3, 7:01 AM CDT	Mesoscale Discussion	SPC	Becker, Cass, Clay, Clearwater, Douglas, Grant and 8 more	119 min
Jul 3, 6:16 PM CDT	Mesoscale Discussion	SPC	Big Stone, Lac qui Parle, Lincoln, Traverse, Wilkin	2 hr
Jul 2, 7:59 PM CDT	Severe Thunderstorm Watch	SPC	Big Horn, Carter, Custer, Fallon, Powder River, Rosebud and 2 more	6 hr
Jul 3, 12:01 AM CDT	Mesoscale Discussion	SPC	Carter, Custer, Fallon, Powder River	89 min
Jul 3, 3:25 PM CDT	Mesoscale Discussion	SPC	Big Horn, Carter, Powder River	2 hr
Jul 3, 5:42 PM CDT	Severe Thunderstorm Watch	SPC	Carter	7 hr
Jul 3, 6:42 PM CDT	Severe Thunderstorm Watch	SPC	Brown, Clark, Day, Edmunds, Faulk, Hand and 8 more	4 hr

Nearby

Mesoscale Discussions in South Dakota, 2018 Mesoscale Discussions in North Dakota, 2018 Mesoscale Discussions in Montana, 2018 Every mesoscale discussion in 2018

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.