Alert archive / Iowa / Mesoscale Discussions in 2007

Mesoscale Discussion 874

May 23, 200737 counties in Iowa; 8 counties in Minnesota; 7 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at May 23, 2007, 7:42 PM CDT for 37 counties in Iowa; 8 counties in Minnesota; 7 counties in Wisconsin. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 23, 2007, 7:42 PM CDT (00:42 UTC)
Expired: May 23, 2007, 9:45 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 52 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Black Hawk County, IA, Bremer County, IA, Butler County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clarke County, IA, Davis County, IA, Decatur County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Howard County, IA, Jasper County, IA, Keokuk County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mitchell County, IA, Monroe County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Winneshiek County, IA, Worth County, IA, Dodge County, MN, Fillmore County, MN, Freeborn County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN, Buffalo County, WI, Clark County, WI, Eau Claire County, WI, Jackson County, WI, La Crosse County, WI, Pepin County, WI, Trempealeau County, WI

The radar

The Des Moines radar (KDMX), 147 km from the middle of the area, began a volume at 00:43 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

Davenport, (KDVN), launched 00:00Z, 0.7 hours before the alert went out and 196 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: 185 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 2153 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 76 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
May 23, 7:10 PM CDT	Mesoscale Discussion	SPC	Fremont, Mills, Montgomery, Page, Pottawattamie, Taylor	35 min
May 24, 1:51 AM CDT	Mesoscale Discussion	SPC	Decatur, Page, Ringgold, Taylor	54 min
May 24, 12:52 PM CDT	Mesoscale Discussion	SPC	Adams, Brown, Calumet, Clark, Columbia, Dane and 29 more	113 min
May 24, 2:25 PM CDT	Severe Thunderstorm Watch	SPC	Brown, Calumet, Door, Florence, Forest, Kewaunee and 16 more	5 hr
May 24, 6:11 PM CDT	Mesoscale Discussion	SPC	Adams, Brown, Calumet, Door, Florence, Forest and 18 more	64 min

Nearby

Mesoscale Discussions in Iowa, 2007 Mesoscale Discussions in Minnesota, 2007 Mesoscale Discussions in Wisconsin, 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.