Alert archive / Iowa / Mesoscale Discussions in 2020
Mesoscale Discussion 1679
The Storm Prediction Center issued this mesoscale discussion at Sep 6, 2020, 5:30 AM CDT for 11 counties in Illinois; 37 counties in Iowa. It was in force for 90 min.
The area
The outline as issued.
The facts
- Issued
- Sep 6, 2020, 5:30 AM CDT (10:30 UTC)
- Expired
- Sep 6, 2020, 7:00 AM CDT
- In force
- 90 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 487
All 48 counties
Benton County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cedar County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clinton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Humboldt County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Johnson County, IA, Jones County, IA, Linn County, IA, Louisa County, IA, Marshall County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Story County, IA, Tama County, IA, Washington County, IA, Webster County, IA, Winnebago County, IA, Wright County, IA, Bureau County, IL, Carroll County, IL, Henry County, IL, Jo Daviess County, IL, Knox County, IL, Mercer County, IL, Peoria County, IL, Rock Island County, IL, Stark County, IL, Stephenson County, IL, Whiteside County, IL
The radar
The Des Moines radar (KDMX), 126 km from the middle of the area, began a volume at 10:32 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
Davenport, (KDVN), launched 00:00Z, 10.5 hours before the alert went out and 155 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2140 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 67 m²/s²
- 0-3 km storm-relative helicity
- 269 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 6, 2:32 AM CDT | Mesoscale Discussion | SPC | Carroll, Henderson, Henry, Jo Daviess, Knox, Lee and 4 more | 88 min |
| Sep 6, 2:53 AM CDT | Severe Thunderstorm Watch | SPC | Bureau, Carroll, DeWitt, Henry, Jo Daviess, Knox and 16 more | 6 hr |
| Sep 5, 7:53 PM CDT | Mesoscale Discussion | SPC | Allamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 19 more | 2 hr |
| Sep 5, 9:34 PM CDT | Severe Thunderstorm Watch | SPC | Allamakee, Benton, Black Hawk, Boone, Bremer, Buchanan and 47 more | 7 hr |
| Sep 5, 11:26 PM CDT | Mesoscale Discussion | SPC | Benton, Black Hawk, Bremer, Buchanan, Butler, Cerro Gordo and 28 more | 94 min |
| Sep 6, 1:06 AM CDT | Mesoscale Discussion | SPC | Allamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 28 more | 84 min |
Nearby
Mesoscale Discussions in Iowa, 2020Mesoscale Discussions in Illinois, 2020Every mesoscale discussion in 2020
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.