Alert archive / North Dakota / Mesoscale Discussions in 2007

Mesoscale Discussion 1682

August 8, 20079 counties in North Dakota; 4 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 8, 2007, 6:40 AM MDT for 9 counties in North Dakota; 4 counties in South Dakota. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Aug 8, 2007, 6:40 AM MDT (12:40 UTC)
Expired: Aug 8, 2007, 8:15 AM MDT
In force: 95 min
Issued by: the Storm Prediction Center

Counties Adams County, ND, Burleigh County, ND, Emmons County, ND, Grant County, ND, Hettinger County, ND, Morton County, ND, Oliver County, ND, Sheridan County, ND, Sioux County, ND, Corson County, SD, Dewey County, SD, Perkins County, SD, Ziebach County, SD

The radar

The Bismarck radar (KBIS), 55 km from the middle of the area, began a volume at 12:40 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, 0.7 hours before the alert went out and 262 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: 244 J/kg
Mixed-layer CIN: -248 J/kg
Mixed-layer LCL: 973 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: -18 m²/s²
0-3 km storm-relative helicity: -1 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

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 8, 1:09 PM MDT	Mesoscale Discussion	SPC	Barnes, Benson, Burleigh, Cass, Dickey, Eddy and 27 more	66 min
Aug 8, 1:57 PM MDT	Severe Thunderstorm Watch	SPC	Barnes, Burleigh, Cass, Dickey, Eddy, Emmons and 22 more	6 hr
Aug 8, 5:17 PM MDT	Mesoscale Discussion	SPC	Barnes, Burleigh, Cass, Dickey, Eddy, Emmons and 22 more	58 min
Aug 8, 2:56 PM MDT	Severe Thunderstorm Watch	SPC	Aurora, Beadle, Brown, Brule, Buffalo, Charles Mix and 17 more	5 hr

Nearby

Mesoscale Discussions in North Dakota, 2007 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.