Alert archive / Minnesota / Mesoscale Discussions in 2011

Mesoscale Discussion 1715

July 23, 201112 counties in Iowa; 18 counties in Minnesota

The Storm Prediction Center issued this mesoscale discussion at Jul 23, 2011, 8:40 PM CDT for 12 counties in Iowa; 18 counties in Minnesota. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Jul 23, 2011, 8:40 PM CDT (01:40 UTC)
Expired: Jul 23, 2011, 10:15 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center

All 30 counties

Cerro Gordo County, IA, Dickinson County, IA, Emmet County, IA, Floyd County, IA, Hancock County, IA, Howard County, IA, Kossuth County, IA, Mitchell County, IA, Palo Alto County, IA, Winnebago County, IA, Winneshiek County, IA, Worth County, IA, Blue Earth County, MN, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Goodhue County, MN, Houston County, MN, Jackson County, MN, Le Sueur County, MN, Martin County, MN, Mower County, MN, Olmsted County, MN, Rice County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Watonwan County, MN, Winona County, MN

The radar

The Minneapolis radar (KMPX), 136 km from the middle of the area, began a volume at 01:42 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

Minneapolis, MN (KMPX), launched 00:00Z, 1.7 hours before the alert went out and 136 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: 2128 J/kg
Mixed-layer CIN: -41 J/kg
Mixed-layer LCL: 814 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 94 m²/s²
0-3 km storm-relative helicity: 212 m²/s²
Significant tornado parameter: 2.0
Supercell composite: 11.7

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
Jul 23, 11:46 PM CDT	Mesoscale Discussion	SPC	Dakota, Dodge, Fillmore, Freeborn, Goodhue, Houston and 7 more	89 min

Nearby

Mesoscale Discussions in Minnesota, 2011 Mesoscale Discussions in Iowa, 2011 Every mesoscale discussion in 2011

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.