Alert archive / Iowa / Mesoscale Discussions in 2004

Mesoscale Discussion 358

April 17, 200414 counties in Iowa; 13 counties in Minnesota

The Storm Prediction Center issued this mesoscale discussion at Apr 17, 2004, 9:31 PM CDT for 14 counties in Iowa; 13 counties in Minnesota. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued
Apr 17, 2004, 9:31 PM CDT (02:31 UTC)
Expired
Apr 17, 2004, 11:30 PM CDT
In force
119 min
Issued by
the Storm Prediction Center
All 27 counties

Allamakee County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Emmet County, IA, Fayette County, IA, Floyd County, IA, Hancock County, IA, Howard County, IA, Kossuth County, IA, Mitchell County, IA, Palo Alto County, IA, Winnebago County, IA, Winneshiek County, IA, Worth County, IA, Blue Earth County, MN, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Houston County, MN, Martin County, MN, Mower County, MN, Olmsted County, MN, Steele County, MN, Waseca County, MN, Watonwan County, MN, Winona County, MN

The radar

The Minneapolis radar (KMPX), 164 km from the middle of the area, began a volume at 02:34 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.5 hours before the alert went out and 165 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, Minneapolis, MN at 00:00Z on 2004-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 2004-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 91 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2026 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
91 m²/s²
0-3 km storm-relative helicity
489 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

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.

IssuedProductOfficeCountiesLasted
Apr 17, 7:45 PM CDTSevere Thunderstorm WatchSPCAllamakee, Cerro Gordo, Chickasaw, Emmet, Floyd, Hancock and 7 more5 hr
Apr 17, 10:05 PM CDTTornado WatchSPCAllamakee, Black Hawk, Bremer, Buchanan, Butler, Cerro Gordo and 19 more5 hr
Apr 17, 11:10 PM CDTMesoscale DiscussionSPCBuena Vista, Cherokee, Clay, Dickinson, Lyon, O'Brien and 3 more95 min
Apr 17, 11:35 PM CDTSevere Thunderstorm WatchSPCClay, Dickinson, Lyon, O'Brien, Osceola, Sioux5 hr
Apr 17, 11:50 PM CDTMesoscale DiscussionSPCCerro Gordo, Emmet, Hancock, Howard, Humboldt, Kossuth and 5 more85 min
Apr 18, 4:15 PM CDTMesoscale DiscussionSPCBuena Vista, Calhoun, Cerro Gordo, Cherokee, Clay, Dickinson and 20 more60 min
Apr 18, 4:40 PM CDTTornado WatchSPCAudubon, Buena Vista, Calhoun, Carroll, Cass, Cherokee and 29 more5 hr
Apr 18, 12:30 AM CDTSevere Thunderstorm WatchSPCAnoka, Carver, Chisago, Dakota, Goodhue, Hennepin and 11 more5 hr
Apr 18, 2:37 AM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Big Stone, Brown, Carlton and 40 more53 min
Apr 18, 4:43 AM CDTMesoscale DiscussionSPCAitkin, Benton, Carlton, Cass, Chisago, Crow Wing and 15 more32 min
Apr 18, 8:04 AM CDTMesoscale DiscussionSPCAitkin, Benton, Carlton, Cass, Crow Wing, Douglas and 6 more86 min
Apr 18, 12:39 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Big Stone, Carlton, Carver and 32 more2 hr
Apr 18, 1:40 PM CDTTornado WatchSPCAitkin, Anoka, Benton, Carlton, Carver, Chippewa and 32 more6 hr
Apr 18, 2:20 PM CDTSevere Thunderstorm WatchSPCLincoln, Lyon, Pipestone, Rock6 hr
Apr 18, 3:33 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Carlton, Chisago, Crow Wing and 12 more117 min
Apr 18, 5:23 PM CDTMesoscale DiscussionSPCLincoln, Lyon, Pipestone, Rock2 hr
Apr 18, 6:35 PM CDTTornado WatchSPCBrown, Carver, Dakota, Goodhue, Hennepin, Le Sueur and 7 more5 hr

Nearby

Mesoscale Discussions in Iowa, 2004Mesoscale Discussions in Minnesota, 2004Every mesoscale discussion in 2004

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.