Alert archive / South Dakota / Mesoscale Discussions in 2007

Mesoscale Discussion 2039

September 30, 200720 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Sep 30, 2007, 1:37 AM CDT for 20 counties in South Dakota. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued: Sep 30, 2007, 1:37 AM CDT (06:37 UTC)
Expired: Sep 30, 2007, 2:30 AM CDT
In force: 53 min
Issued by: the Storm Prediction Center

Counties Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brookings County, SD, Brule County, SD, Buffalo County, SD, Charles Mix County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hand County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Lyman County, SD, McCook County, SD, Miner County, SD, Sanborn County, SD

The radar

The Sioux Falls radar (KFSD), 148 km from the middle of the area, began a volume at 06:39 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, 6.6 hours before the alert went out and 130 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: 1496 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 2061 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 143 m²/s²
0-3 km storm-relative helicity: 131 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.7

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
Sep 29, 7:26 PM CDT	Mesoscale Discussion	SPC	Bennett, Brule, Buffalo, Edmunds, Faulk, Hand and 11 more	64 min
Sep 29, 9:28 PM CDT	Severe Thunderstorm Watch	SPC	Aurora, Beadle, Bon Homme, Brookings, Brule, Buffalo and 14 more	6 hr
Sep 30, 11:01 AM CDT	Mesoscale Discussion	SPC	Bon Homme, Clay, Lincoln, Turner, Union, Yankton	59 min
Sep 30, 1:02 PM CDT	Tornado Watch	SPC	Clay, Lincoln, Turner, Union, Yankton	7 hr
Sep 30, 3:36 PM CDT	Mesoscale Discussion	SPC	Clay, Lincoln, Minnehaha, Moody, Turner, Union	54 min

Nearby

Mesoscale Discussions in South Dakota, 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.