Alert archive / Iowa / Mesoscale Discussions in 2019

Mesoscale Discussion 2012

September 24, 20194 states

The Storm Prediction Center issued this mesoscale discussion at Sep 24, 2019, 6:33 PM CDT for 4 states. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued
Sep 24, 2019, 6:33 PM CDT (23:33 UTC)
Expired
Sep 24, 2019, 8:30 PM CDT
In force
117 min
Issued by
the Storm Prediction Center
All 90 counties

Adair County, IA, Adams County, IA, Audubon County, IA, Boone County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Cherokee County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Dickinson County, IA, Emmet County, IA, Floyd County, IA, Franklin County, IA, Fremont County, IA, Greene County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Harrison County, IA, Humboldt County, IA, Ida County, IA, Kossuth County, IA, Madison County, IA, Mills County, IA, Mitchell County, IA, Monona County, IA, Montgomery County, IA, O'Brien County, IA, Palo Alto County, IA, Pocahontas County, IA, Polk County, IA, Pottawattamie County, IA, Sac County, IA, Shelby County, IA, Story County, IA, Union County, IA, Webster County, IA, Winnebago County, IA, Woodbury County, IA, Worth County, IA, Wright County, IA, Anoka County, MN, Blue Earth County, MN, Brown County, MN, Carver County, MN, Chisago County, MN, Cottonwood County, MN, Dakota County, MN, Dodge County, MN, Faribault County, MN, Freeborn County, MN, Goodhue County, MN, Hennepin County, MN, Jackson County, MN, Le Sueur County, MN, Martin County, MN, McLeod County, MN, Meeker County, MN, Mower County, MN, Nicollet County, MN, Olmsted County, MN, Ramsey County, MN, Rice County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Washington County, MN, Watonwan County, MN, Wright County, MN, Burt County, NE, Cass County, NE, Douglas County, NE, Lancaster County, NE, Sarpy County, NE, Saunders County, NE, Washington County, NE, Barron County, WI, Dunn County, WI, Pepin County, WI, Pierce County, WI, Polk County, WI, Saint Croix County, WI

The radar

The Des Moines radar (KDMX), 133 km from the middle of the area, began a volume at 23:32 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

Omaha, NE (KOAX), launched 12:00Z, 11.6 hours before the alert went out and 201 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-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2019-09-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 498 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2019-09-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 241 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
498 J/kg
Mixed-layer CIN
-185 J/kg
Mixed-layer LCL
1159 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
241 m²/s²
0-3 km storm-relative helicity
245 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

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.

IssuedProductOfficeCountiesLasted
Sep 24, 3:13 PM CDTMesoscale DiscussionSPCAllamakee, Bremer, Buena Vista, Butler, Cerro Gordo, Chickasaw and 17 more3 hr
Sep 24, 4:43 PM CDTTornado WatchSPCAdair, Adams, Audubon, Boone, Buena Vista, Butler and 55 more7 hr
Sep 24, 5:16 PM CDTMesoscale DiscussionSPCBeltrami, Clearwater, Kittson, Koochiching, Lake of the Woods, Mahnomen and 6 more2 hr
Sep 24, 5:30 PM CDTMesoscale DiscussionSPCGage, Jefferson, Johnson, Lancaster, Nemaha, Otoe and 4 more60 min
Sep 24, 5:42 PM CDTSevere Thunderstorm WatchSPCGage, Jefferson, Johnson, Lancaster, Nemaha, Otoe and 3 more6 hr
Sep 24, 6:52 PM CDTMesoscale DiscussionSPCAshland, Chippewa, Clark, Florence, Forest, Iron and 17 more53 min

Nearby

Mesoscale Discussions in Iowa, 2019Mesoscale Discussions in Minnesota, 2019Mesoscale Discussions in Nebraska, 2019Every 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.