Alert archive / North Dakota / Mesoscale Discussions in 2015

Mesoscale Discussion 1508

July 23, 201511 counties in North Dakota; Corson County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 23, 2015, 1:34 PM CDT for 11 counties in North Dakota; Corson County, South Dakota. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued: Jul 23, 2015, 1:34 PM CDT (18:34 UTC)
Expired: Jul 23, 2015, 3:30 PM CDT
In force: 116 min
Issued by: the Storm Prediction Center
Chance of a watch: 60%

Counties Burleigh County, ND, Emmons County, ND, Grant County, ND, McHenry County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Oliver County, ND, Sheridan County, ND, Sioux County, ND, Ward County, ND, Corson County, SD

The radar

The Bismarck radar (KBIS), 49 km from the middle of the area, began a volume at 18:34 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.

Severe Thunderstorm Watch 448Jul 23, 3:55 PM CDT

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 6.6 hours before the alert went out and 52 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: 785 J/kg
Mixed-layer CIN: -292 J/kg
Mixed-layer LCL: 1367 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 71 m²/s²
0-3 km storm-relative helicity: 158 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
Jul 23, 3:58 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Barnes, Benson, Bottineau, Burleigh, Cass and 39 more	11 hr
Jul 23, 6:21 PM CDT	Mesoscale Discussion	SPC	Benson, Burleigh, Emmons, Grant, Kidder, McHenry and 10 more	24 min
Jul 23, 2:34 PM CDT	Mesoscale Discussion	SPC	Brule, Gregory, Tripp	56 min
Jul 23, 3:04 PM CDT	Severe Thunderstorm Watch	SPC	Charles Mix, Douglas, Gregory, Tripp	8 hr
Jul 23, 6:55 PM CDT	Mesoscale Discussion	SPC	Gregory	2 hr

Nearby

Mesoscale Discussions in North Dakota, 2015 Mesoscale Discussions in South Dakota, 2015 Every mesoscale discussion in 2015

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.