Alert archive / South Dakota / Mesoscale Discussions in 2006

Mesoscale Discussion 1849

August 20, 20064 states

The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2006, 8:00 PM CDT for 4 states. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Aug 20, 2006, 8:00 PM CDT (01:00 UTC)
Expired: Aug 20, 2006, 9:30 PM CDT
In force: 90 min
Issued by: the Storm Prediction Center

All 48 counties

Kittson County, MN, Roseau County, MN, Barnes County, ND, Cass County, ND, Dickey County, ND, Eddy County, ND, Foster County, ND, Grand Forks County, ND, Griggs County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Nelson County, ND, Pembina County, ND, Ransom County, ND, Sargent County, ND, Steele County, ND, Stutsman County, ND, Walsh County, ND, Cherry County, NE, Sheridan County, NE, Aurora County, SD, Beadle County, SD, Bennett County, SD, Brown County, SD, Brule County, SD, Buffalo County, SD, Campbell County, SD, Clark County, SD, Day County, SD, Edmunds County, SD, Faulk County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jerauld County, SD, Jones County, SD, Lyman County, SD, Marshall County, SD, McPherson County, SD, Mellette County, SD, Potter County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Todd County, SD, Tripp County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 41 km from the middle of the area, began a volume at 01:03 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 00:00Z, 1.0 hours before the alert went out and 100 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: 827 J/kg
Mixed-layer CIN: -113 J/kg
Mixed-layer LCL: 1412 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 155 m²/s²
0-3 km storm-relative helicity: 243 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 5.4

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
Aug 21, 1:54 PM CDT	Mesoscale Discussion	SPC	Banner, Box Butte, Cheyenne, Dawes, Kimball, Morrill and 3 more	2 hr

Nearby

Mesoscale Discussions in South Dakota, 2006 Mesoscale Discussions in North Dakota, 2006 Mesoscale Discussions in Minnesota, 2006 Every mesoscale discussion in 2006

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.