Alert archive / South Dakota / Mesoscale Discussions in 2018

Mesoscale Discussion 753

June 16, 201811 counties in Nebraska; 20 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jun 16, 2018, 2:15 PM MDT for 11 counties in Nebraska; 20 counties in South Dakota. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Jun 16, 2018, 2:15 PM MDT (20:15 UTC)
Expired: Jun 16, 2018, 3:45 PM MDT
In force: 90 min
Issued by: the Storm Prediction Center
Chance of a watch: 95%

All 31 counties

Banner County, NE, Box Butte County, NE, Cherry County, NE, Cheyenne County, NE, Dawes County, NE, Garden County, NE, Grant County, NE, Morrill County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Bennett County, SD, Brule County, SD, Buffalo County, SD, Edmunds County, SD, Faulk County, SD, Haakon County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jackson County, SD, Jerauld County, SD, Jones County, SD, Lyman County, SD, Mellette County, SD, Oglala Lakota County, SD, Potter County, SD, Stanley County, SD, Sully County, SD, Todd County, SD, Tripp County, SD

The radar

The North Platte radar (KLNX), 145 km from the middle of the area, began a volume at 20:14 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.

Severe Thunderstorm Watch 181Jun 16, 2:50 PM MDT

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 8.3 hours before the alert went out and 298 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: 177 J/kg
Mixed-layer CIN: -361 J/kg
Mixed-layer LCL: 1088 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 283 m²/s²
0-3 km storm-relative helicity: 383 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 9.2

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
Jun 16, 2:54 PM MDT	Severe Thunderstorm Watch	SPC	Banner, Box Butte, Cheyenne, Dawes, Kimball, Morrill and 2 more	7 hr
Jun 16, 5:14 PM MDT	Mesoscale Discussion	SPC	Arthur, Banner, Box Butte, Cherry, Cheyenne, Dawes and 7 more	91 min
Jun 16, 8:13 AM MDT	Mesoscale Discussion	SPC	Brown, Campbell, Corson, Dewey, Edmunds, Faulk and 4 more	92 min
Jun 16, 2:06 PM MDT	Mesoscale Discussion	SPC	Beadle, Brookings, Brown, Clark, Codington, Day and 7 more	84 min
Jun 16, 2:38 PM MDT	Tornado Watch	SPC	Beadle, Brown, Clark, Codington, Day, Deuel and 6 more	8 hr
Jun 16, 5:21 PM MDT	Mesoscale Discussion	SPC	Beadle, Brookings, Brown, Clark, Codington, Day and 7 more	114 min

Nearby

Mesoscale Discussions in South Dakota, 2018 Mesoscale Discussions in Nebraska, 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.