Alert archive / Iowa / Mesoscale Discussions in 2016

Mesoscale Discussion 1374

July 23, 201614 counties in Iowa; Crawford County, Grant County, Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jul 23, 2016, 2:08 PM CDT for 14 counties in Iowa; Crawford County, Grant County, Wisconsin. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jul 23, 2016, 2:08 PM CDT (19:08 UTC)
Expired: Jul 23, 2016, 4:45 PM CDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Allamakee County, IA, Benton County, IA, Buchanan County, IA, Cedar County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Iowa County, IA, Jackson County, IA, Johnson County, IA, Jones County, IA, Linn County, IA, Crawford County, WI, Grant County, WI

The radar

The Quad Cities radar (KDVN), 110 km from the middle of the area, began a volume at 19:09 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 412Jul 23, 3:20 PM CDT

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 7.1 hours before the alert went out and 114 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: 2607 J/kg
Mixed-layer CIN: -89 J/kg
Mixed-layer LCL: 807 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 83 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 23, 8:58 AM CDT	Mesoscale Discussion	SPC	Allamakee, Clayton, Fayette, Howard, Winneshiek	3 hr
Jul 23, 2:50 PM CDT	Mesoscale Discussion	SPC	Clayton, Delaware, Dubuque, Jackson, Jones	25 min
Jul 23, 3:23 PM CDT	Severe Thunderstorm Watch	SPC	Benton, Buchanan, Cedar, Clayton, Clinton, Delaware and 8 more	7 hr
Jul 23, 5:25 PM CDT	Mesoscale Discussion	SPC	Clinton, Jackson, Scott	2 hr
Jul 23, 1:06 PM CDT	Mesoscale Discussion	SPC	Dane, Green, Jefferson, Kenosha, Rock, Walworth and 1 more	2 hr

Nearby

Mesoscale Discussions in Iowa, 2016 Mesoscale Discussions in Wisconsin, 2016 Every mesoscale discussion in 2016

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.