Alert archive / South Dakota / Mesoscale Discussions in 2007

Mesoscale Discussion 704

May 5, 20074 counties in Iowa; 8 counties in Nebraska; 9 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at May 5, 2007, 1:01 PM CDT for 4 counties in Iowa; 8 counties in Nebraska; 9 counties in South Dakota. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: May 5, 2007, 1:01 PM CDT (18:01 UTC)
Expired: May 5, 2007, 2:30 PM CDT
In force: 89 min
Issued by: the Storm Prediction Center

All 21 counties

Lyon County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Boyd County, NE, Cedar County, NE, Dakota County, NE, Dixon County, NE, Holt County, NE, Knox County, NE, Pierce County, NE, Wayne County, NE, Bon Homme County, SD, Charles Mix County, SD, Clay County, SD, Douglas County, SD, Hutchinson County, SD, Lincoln County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 100 km from the middle of the area, began a volume at 18:01 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.

Tornado Watch 236May 5, 4:35 PM CDT

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 6.0 hours before the alert went out and 225 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: 302 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 521 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 177 m²/s²
0-3 km storm-relative helicity: 165 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 5, 10:35 AM CDT	Mesoscale Discussion	SPC	Buena Vista, Carroll, Cherokee, Clay, Crawford, Dickinson and 12 more	85 min
May 5, 10:55 AM CDT	Tornado Watch	SPC	Cherokee, Ida, Lyon, Monona, O'Brien, Osceola and 3 more	6 hr
May 5, 2:42 PM CDT	Tornado Watch PDS	SPC	Fremont, Harrison, Mills, Montgomery, Page, Pottawattamie and 1 more	7 hr
May 5, 4:09 PM CDT	Mesoscale Discussion	SPC	Lyon, Plymouth, Sioux, Woodbury	96 min
May 5, 4:33 PM CDT	Tornado Watch PDS	SPC	Cherokee, Ida, Lyon, Monona, O'Brien, Osceola and 3 more	6 hr
May 4, 7:26 PM CDT	Tornado Watch	SPC	Adams, Blaine, Boyd, Brown, Buffalo, Clay and 28 more	7 hr
May 4, 8:29 PM CDT	Mesoscale Discussion	SPC	Chase, Dundy, Hayes, Hitchcock, Perkins	91 min
May 4, 8:49 PM CDT	Mesoscale Discussion	SPC	Antelope, Cedar, Dixon, Knox, Madison, Pierce and 1 more	56 min
May 4, 9:22 PM CDT	Tornado Watch	SPC	Antelope, Boone, Cedar, Knox, Pierce	11 hr
May 4, 9:41 PM CDT	Mesoscale Discussion	SPC	Adams, Blaine, Brown, Buffalo, Custer, Franklin and 16 more	94 min
May 4, 10:34 PM CDT	Mesoscale Discussion	SPC	Butler, Colfax, Cuming, Dodge, Gage, Jefferson and 8 more	56 min
May 4, 11:28 PM CDT	Mesoscale Discussion	SPC	Chase, Dundy, Hayes, Perkins	92 min
May 5, 1:23 AM CDT	Mesoscale Discussion	SPC	Adams, Antelope, Blaine, Boone, Brown, Buffalo and 52 more	67 min
May 5, 1:30 AM CDT	Tornado Watch	SPC	Adams, Antelope, Arthur, Blaine, Boone, Boyd and 60 more	7 hr
May 5, 3:00 AM CDT	Mesoscale Discussion	SPC	Adams, Antelope, Arthur, Blaine, Boone, Boyd and 60 more	90 min
May 5, 6:59 AM CDT	Mesoscale Discussion	SPC	Adams, Antelope, Boone, Buffalo, Butler, Cedar and 41 more	61 min
May 5, 8:52 AM CDT	Mesoscale Discussion	SPC	Frontier, Furnas, Harlan, Hayes, Hitchcock, Red Willow	53 min
May 5, 9:51 AM CDT	Tornado Watch PDS	SPC	Adams, Blaine, Boone, Buffalo, Chase, Clay and 34 more	12 hr
May 5, 11:32 AM CDT	Mesoscale Discussion	SPC	Adams, Buffalo, Dawson, Franklin, Furnas, Gosper and 4 more	88 min
May 5, 1:45 PM CDT	Mesoscale Discussion	SPC	Arthur, Box Butte, Cherry, Dawes, Deuel, Garden and 8 more	2 hr
May 5, 2:32 PM CDT	Mesoscale Discussion	SPC	Butler, Cass, Colfax, Cuming, Dodge, Fillmore and 14 more	28 min

Nearby

Mesoscale Discussions in South Dakota, 2007 Mesoscale Discussions in Nebraska, 2007 Mesoscale Discussions in Iowa, 2007 Every mesoscale discussion in 2007

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.