Alert archive / Illinois / Tornado Watches in 2025
Tornado Watch 255
The Storm Prediction Center issued this tornado watch at May 15, 2025, 5:15 PM CDT for 43 counties in Illinois; 5 counties in Indiana. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- May 15, 2025, 5:15 PM CDT (22:15 UTC)
- Expired
- May 15, 2025, 9:30 PM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 65 kt
All 48 counties
Bureau County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Coles County, IL, Cook County, IL, Cumberland County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Edgar County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Iroquois County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Moultrie County, IL, Ogle County, IL, Peoria County, IL, Piatt County, IL, Putnam County, IL, Sangamon County, IL, Shelby County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Will County, IL, Woodford County, IL, Benton County, IN, Jasper County, IN, Lake County, IN, Newton County, IN, Porter County, IN
The radar
The Chicago radar (KLOT), 43 km from the middle of the area, began a volume at 22:16 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 50%
- One or more EF2 to EF5 tornadoes
- 30%
- Ten or more severe wind reports
- 60%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 60%
- One or more hailstones of 2 inches or more
- 60%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
26 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 5:27 PM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry, Whiteside | 33 min |
| May 15, 5:33 PM CDT | Severe Thunderstorm Warning | LOT | Lee | 43 min |
| May 15, 5:35 PM CDT | Severe Thunderstorm Warning | ILX | Knox, Peoria, Stark | 40 min |
| May 15, 5:52 PM CDT | Severe Thunderstorm Warning | LOT | Ogle | 53 min |
| May 15, 5:57 PM CDT | Severe Thunderstorm Warning | LOT | Boone, DeKalb, McHenry, Ogle, Winnebago | 71 min |
| May 15, 6:12 PM CDT | Severe Thunderstorm Warning | ILX | Logan, Menard, Sangamon | 48 min |
| May 15, 6:15 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Lake | 45 min |
| May 15, 6:23 PM CDT | Severe Thunderstorm Warning | ILX | Logan, Mason, Menard, Tazewell | 37 min |
| May 15, 6:26 PM CDT | Severe Thunderstorm Warning | ILX | Logan, Sangamon | 49 min |
| May 15, 6:29 PM CDT | Severe Thunderstorm Warning | ILX | Marshall, Peoria, Tazewell, Woodford | 46 min |
| May 15, 6:40 PM CDT | Severe Thunderstorm Warning | LOT | DeKalb, Kane, McHenry | 28 min |
| May 15, 6:44 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Logan, McLean | 46 min |
| May 15, 6:52 PM CDT | Severe Thunderstorm Warning | ILX | McLean | 53 min |
| May 15, 7:08 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Livingston | 54 min |
| May 15, 7:12 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Logan, Macon, Sangamon | 32 min |
| May 15, 7:19 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Logan, Macon | 41 min |
| May 15, 7:29 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Lake | 46 min |
| May 15, 7:33 PM CDT | Tornado Warning | ILX | Macon | 27 min |
| May 15, 7:35 PM CDT | Severe Thunderstorm Warning | LOT | Grundy, Kankakee, Livingston, Will | 28 min |
| May 15, 7:45 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Grundy, Kankakee, Livingston, Will | 60 min |
| May 15, 7:48 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Will | 57 min |
| May 15, 7:50 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Macon, Piatt | 25 min |
| May 15, 7:54 PM CDT | Tornado Warning | ILX | Macon, Piatt | 36 min |
| May 15, 8:01 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Will | 29 min |
| May 15, 8:13 PM CDT | Severe Thunderstorm Warning | LOT | Lake, Porter | 62 min |
| May 15, 8:34 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Vermilion | 19 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 10.3 hours before the alert went out and 124 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
- 1872 J/kg
- Mixed-layer CIN
- -124 J/kg
- Mixed-layer LCL
- 764 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 197 m²/s²
- 0-3 km storm-relative helicity
- 206 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.3
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 2:14 PM CDT | Mesoscale Discussion | SPC | Boone, Carroll, DeKalb, Jo Daviess, Lee, McHenry and 4 more | 2 hr |
| May 15, 3:05 PM CDT | Tornado Watch | SPC | Boone, Jo Daviess, McHenry, Stephenson, Winnebago | 6 hr |
| May 15, 3:07 PM CDT | Mesoscale Discussion | SPC | Massac, Pulaski | 83 min |
| May 15, 3:22 PM CDT | Mesoscale Discussion | SPC | Bureau, Christian, DeKalb, DeWitt, Ford, Grundy and 21 more | 113 min |
| May 15, 6:50 PM CDT | Mesoscale Discussion | SPC | Allen, Benton, Blackford, Boone, Carroll, Cass and 33 more | 85 min |
Nearby
Tornado Watches in Illinois, 2025Tornado Watches in Indiana, 2025Every tornado watch in 2025
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.