Alert archive / South Dakota / Mesoscale Discussions in 2009

Mesoscale Discussion 897

May 29, 200913 counties in Nebraska; Emmons County, Sioux County, North Dakota; 19 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at May 29, 2009, 6:15 PM CDT for 13 counties in Nebraska; Emmons County, Sioux County, North Dakota; 19 counties in South Dakota. It was in force for 60 min.

The area

The outline as issued.

The facts

Issued: May 29, 2009, 6:15 PM CDT (23:15 UTC)
Expired: May 29, 2009, 7:15 PM CDT
In force: 60 min
Issued by: the Storm Prediction Center

All 34 counties

Emmons County, ND, Sioux County, ND, Blaine County, NE, Brown County, NE, Cherry County, NE, Custer County, NE, Garfield County, NE, Holt County, NE, Keya Paha County, NE, Logan County, NE, Loup County, NE, Rock County, NE, Thomas County, NE, Valley County, NE, Wheeler County, NE, Campbell County, SD, Corson County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Haakon County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jones County, SD, Lyman County, SD, McPherson County, SD, Mellette County, SD, Potter County, SD, Stanley County, SD, Sully County, SD, Todd County, SD, Tripp County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 203 km from the middle of the area, began a volume at 23:19 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 11.3 hours before the alert went out and 315 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1998 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 36 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 29, 2:07 PM CDT	Mesoscale Discussion	SPC	Barnes, Benson, Cass, Cavalier, Eddy, Foster and 12 more	83 min

Nearby

Mesoscale Discussions in South Dakota, 2009 Mesoscale Discussions in Nebraska, 2009 Mesoscale Discussions in North Dakota, 2009 Every mesoscale discussion in 2009

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.