Alert archive / Indiana / Mesoscale Discussions in 2026
Mesoscale Discussion 488
The Storm Prediction Center issued this mesoscale discussion at Apr 17, 2026, 10:19 PM CDT for 7 counties in Illinois; 26 counties in Indiana; Berrien County, Michigan. It was in force for 116 min.
The area
The outline as issued.
The facts
- Issued
- Apr 17, 2026, 10:19 PM CDT (03:19 UTC)
- Expired
- Apr 18, 2026, 12:15 AM CDT
- In force
- 116 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 131...133
All 34 counties
Coles County, IL, Douglas County, IL, Edgar County, IL, Iroquois County, IL, Kankakee County, IL, Moultrie County, IL, Vermilion County, IL, Benton County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Jasper County, IN, Kosciusko County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Miami County, IN, Montgomery County, IN, Newton County, IN, Parke County, IN, Porter County, IN, Pulaski County, IN, Putnam County, IN, Saint Joseph County, IN, Starke County, IN, Tippecanoe County, IN, Vermillion County, IN, Vigo County, IN, Warren County, IN, White County, IN, Berrien County, MI
The radar
The Chicago radar (KLOT), 115 km from the middle of the area, began a volume at 03:18 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 00:00Z, 3.3 hours before the alert went out and 133 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
- 1309 J/kg
- Mixed-layer CIN
- -103 J/kg
- Mixed-layer LCL
- 1221 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 212 m²/s²
- 0-3 km storm-relative helicity
- 264 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 8.2
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 |
|---|---|---|---|---|
| Apr 17, 8:09 PM CDT | Mesoscale Discussion | SPC | Cass, Champaign, Christian, Clark, Coles, Cook and 36 more | 2 hr |
| Apr 17, 8:39 PM CDT | Mesoscale Discussion | SPC | Bond, Calhoun, Christian, Clinton, Fayette, Greene and 6 more | 2 hr |
| Apr 17, 8:52 PM CDT | Mesoscale Discussion | SPC | Champaign, DeWitt, Ford, Iroquois, Logan, McLean and 3 more | 83 min |
| Apr 17, 9:44 PM CDT | Tornado Watch | SPC | Boone, Carroll, Cass, Clay, Clinton, Elkhart and 19 more | 3 hr |
Nearby
Mesoscale Discussions in Indiana, 2026Mesoscale Discussions in Illinois, 2026Mesoscale Discussions in Michigan, 2026Every mesoscale discussion in 2026
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.