Alert archive / Iowa / Mesoscale Discussions in 2012
Mesoscale Discussion 1494
The Storm Prediction Center issued this mesoscale discussion at Jul 18, 2012, 3:07 PM CDT for 4 states. It was in force for 53 min.
The area
The outline as issued.
The facts
- Issued
- Jul 18, 2012, 3:07 PM CDT (20:07 UTC)
- Expired
- Jul 18, 2012, 4:00 PM CDT
- In force
- 53 min
- Issued by
- the Storm Prediction Center
All 66 counties
Allamakee County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cedar County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Howard County, IA, Jackson County, IA, Johnson County, IA, Jones County, IA, Linn County, IA, Mitchell County, IA, Muscatine County, IA, Scott County, IA, Tama County, IA, Winneshiek County, IA, Worth County, IA, Boone County, IL, Bureau County, IL, Carroll County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Henry County, IL, Iroquois County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Marshall County, IL, Mercer County, IL, Ogle County, IL, Putnam County, IL, Rock Island County, IL, Stark County, IL, Stephenson County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Fillmore County, MN, Freeborn County, MN, Houston County, MN, Mower County, MN, Crawford County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Lafayette County, WI, Richland County, WI, Rock County, WI, Vernon County, WI
The radar
The Quad Cities radar (KDVN), 74 km from the middle of the area, began a volume at 20:07 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 12:00Z, 8.1 hours before the alert went out and 74 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
- 1900 J/kg
- Mixed-layer CIN
- -67 J/kg
- Mixed-layer LCL
- 1674 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 35 m²/s²
- 0-3 km storm-relative helicity
- 44 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 18, 11:38 AM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, DeKalb, DuPage, Grundy and 11 more | 67 min |
| Jul 18, 12:58 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 22 more | 7 hr |
| Jul 18, 6:56 PM CDT | Mesoscale Discussion | SPC | Boone, Cook, DeKalb, DuPage, Grundy, Jo Daviess and 8 more | 94 min |
Nearby
Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Wisconsin, 2012Every mesoscale discussion in 2012
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.