Alert archive / Minnesota / Mesoscale Discussions in 2016

Mesoscale Discussion 1556

August 18, 201611 counties in Minnesota; 5 counties in North Dakota; Roberts County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 18, 2016, 7:17 AM CDT for 11 counties in Minnesota; 5 counties in North Dakota; Roberts County, South Dakota. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Aug 18, 2016, 7:17 AM CDT (12:17 UTC)
Expired: Aug 18, 2016, 9:45 AM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Becker County, MN, Clay County, MN, Douglas County, MN, Grant County, MN, Otter Tail County, MN, Pope County, MN, Stevens County, MN, Todd County, MN, Traverse County, MN, Wadena County, MN, Wilkin County, MN, Barnes County, ND, Cass County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Roberts County, SD

The radar

The Fargo/Grand Forks radar (KMVX), 135 km from the middle of the area, began a volume at 12:16 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 12:00Z, 0.3 hours before the alert went out and 231 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: 1795 J/kg
Mixed-layer CIN: -157 J/kg
Mixed-layer LCL: 880 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 319 m²/s²
0-3 km storm-relative helicity: 353 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.0

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
Aug 18, 2:31 PM CDT	Mesoscale Discussion	SPC	Blue Earth, Brown, Cottonwood, Dodge, Faribault, Fillmore and 12 more	89 min
Aug 18, 2:46 PM CDT	Severe Thunderstorm Watch	SPC	Blue Earth, Brown, Dodge, Faribault, Fillmore, Freeborn and 13 more	6 hr
Aug 18, 5:48 PM CDT	Mesoscale Discussion	SPC	Fillmore, Houston, Mower, Olmsted, Winona	87 min
Aug 18, 3:30 PM CDT	Mesoscale Discussion	SPC	Aurora, Bon Homme, Brule, Charles Mix, Davison, Douglas and 13 more	2 hr

Nearby

Mesoscale Discussions in Minnesota, 2016 Mesoscale Discussions in North Dakota, 2016 Mesoscale Discussions in South Dakota, 2016 Every mesoscale discussion in 2016

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.