Alert archive / Illinois / Mesoscale Discussions in 2017
Mesoscale Discussion 1508
The Storm Prediction Center issued this mesoscale discussion at Aug 16, 2017, 2:35 PM CDT for 37 counties in Illinois; 24 counties in Iowa; 17 counties in Missouri. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 16, 2017, 2:35 PM CDT (19:35 UTC)
- Expired
- Aug 16, 2017, 5:00 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 78 counties
Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Cedar County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Fayette County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Tama County, IA, Washington County, IA, Adams County, IL, Bond County, IL, Brown County, IL, Bureau County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clinton County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Jersey County, IL, Knox County, IL, Logan County, IL, Macoupin County, IL, Madison County, IL, Mason County, IL, McDonough County, IL, Menard County, IL, Mercer County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Peoria County, IL, Pike County, IL, Rock Island County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Stark County, IL, Tazewell County, IL, Warren County, IL, Washington County, IL, Whiteside County, IL, City of Saint Louis, MO, Clark County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lewis County, MO, Lincoln County, MO, Marion County, MO, Montgomery County, MO, Pike County, MO, Ralls County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Warren County, MO, Washington County, MO
The radar
The Quad Cities radar (KDVN), 128 km from the middle of the area, began a volume at 19:38 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
Lincoln, IL (KILX), launched 12:00Z, 7.6 hours before the alert went out and 210 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
- 487 J/kg
- Mixed-layer CIN
- -60 J/kg
- Mixed-layer LCL
- 877 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 10 m²/s²
- 0-3 km storm-relative helicity
- 38 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 |
|---|---|---|---|---|
| Aug 16, 12:42 PM CDT | Mesoscale Discussion | SPC | Appanoose, Davis, Lee, Monroe, Van Buren, Wapello | 3 hr |
| Aug 16, 2:48 PM CDT | Severe Thunderstorm Watch | SPC | Barton, Bates, Carroll, Cass, Clay, Henry and 8 more | 9 hr |
| Aug 16, 4:47 PM CDT | Mesoscale Discussion | SPC | Barton, Bates, Benton, Cass, Cedar, Dade and 7 more | 88 min |
Nearby
Mesoscale Discussions in Illinois, 2017Mesoscale Discussions in Iowa, 2017Mesoscale Discussions in Missouri, 2017Every mesoscale discussion in 2017
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.