Alert archive / Iowa / Mesoscale Discussions in 2015

Mesoscale Discussion 1522

July 24, 201519 counties in Iowa; 11 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Jul 24, 2015, 6:47 PM CDT for 19 counties in Iowa; 11 counties in Nebraska. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued: Jul 24, 2015, 6:47 PM CDT (23:47 UTC)
Expired: Jul 24, 2015, 8:15 PM CDT
In force: 88 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 30 counties

Adair County, IA, Audubon County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Crawford County, IA, Dallas County, IA, Fremont County, IA, Greene County, IA, Guthrie County, IA, Harrison County, IA, Ida County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Pocahontas County, IA, Pottawattamie County, IA, Sac County, IA, Shelby County, IA, Cass County, NE, Douglas County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Sarpy County, NE, Washington County, NE

The radar

The Omaha radar (KOAX), 42 km from the middle of the area, began a volume at 23:47 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

Topeka, KS (KFOE), launched 12:00Z, 11.8 hours before the alert went out and 236 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: 2454 J/kg
Mixed-layer CIN: -114 J/kg
Mixed-layer LCL: 981 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 93 m²/s²
0-3 km storm-relative helicity: 159 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 24, 5:28 AM CDT	Mesoscale Discussion	SPC	Benton, Black Hawk, Bremer, Buchanan, Butler, Cerro Gordo and 19 more	3 hr
Jul 24, 3:57 PM CDT	Mesoscale Discussion	SPC	Franklin, Frontier, Furnas, Gosper, Harlan, Hitchcock and 5 more	93 min

Nearby

Mesoscale Discussions in Iowa, 2015 Mesoscale Discussions in Nebraska, 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.