Alert archive / Iowa / Mesoscale Discussions in 2019

Mesoscale Discussion 778

May 24, 201911 counties in Iowa; 7 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at May 24, 2019, 7:00 PM CDT for 11 counties in Iowa; 7 counties in Wisconsin. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 24, 2019, 7:00 PM CDT (00:00 UTC)
Expired: May 24, 2019, 9:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Allamakee County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Grundy County, IA, Winneshiek County, IA, Crawford County, WI, Dane County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Lafayette County, WI, Richland County, WI

The radar

The La Crosse radar (KARX), 110 km from the middle of the area, began a volume at 00:02 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.

Tornado Watch 237May 24, 7:50 PM CDT

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 0.0 hours before the alert went out and 145 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 0 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 137 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
May 24, 7:49 PM CDT	Tornado Watch	SPC	Allamakee, Clayton, Fayette, Winneshiek	3 hr
May 24, 8:57 PM CDT	Mesoscale Discussion	SPC	Cedar, Clinton, Delaware, Des Moines, Dubuque, Jackson and 4 more	2 hr
May 24, 9:17 PM CDT	Mesoscale Discussion	SPC	Allamakee, Clayton, Fayette, Winneshiek	118 min
May 25, 3:24 PM CDT	Mesoscale Discussion	SPC	Appanoose, Davis, Des Moines, Henry, Jefferson, Lee and 2 more	3 hr
May 25, 5:23 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Appanoose, Clarke, Davis, Decatur, Lucas and 7 more	6 hr
May 25, 6:48 PM CDT	Mesoscale Discussion	SPC	Des Moines, Henry, Jefferson, Keokuk, Lee, Louisa and 2 more	57 min

Nearby

Mesoscale Discussions in Iowa, 2019 Mesoscale Discussions in Wisconsin, 2019 Every mesoscale discussion in 2019

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.