Alert archive / Illinois / Tornado Warnings in 2026
Tornado Warning 64, NWS Chicago, IL
NWS Chicago, IL issued this tornado warning at Aug 9, 2026, 11:36 PM CDT for LaSalle County, Illinois. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Aug 9, 2026, 11:36 PM CDT (04:36 UTC)
- Expired
- Aug 10, 2026, 12:00 AM CDT
- In force
- 24 min
- Issued by
- NWS Chicago, IL
- Area
- Storm-based polygon
- Tornado
- Radar indicated
- Hail
- 0.75 in
County LaSalle County, IL
The radar
The Chicago radar (KLOT), 73 km from the middle of the area, began a volume at 04:40 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 9, 8:43 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Lincoln, IL (KILX), launched 00:00Z, 4.6 hours before the alert went out and 135 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
- 3443 J/kg
- Mixed-layer CIN
- -45 J/kg
- Mixed-layer LCL
- 949 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 123 m²/s²
- 0-3 km storm-relative helicity
- 334 m²/s²
- Significant tornado parameter
- 2.1
- Supercell composite
- 13.5
What forecasters said that day
The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Chicago, IL wrote its last area forecast discussion before this tornado warning went out at Aug 9, 7:21 PM CDT, 4 hours 15 minutes earlier.
Area forecast discussion, Aug 9, 7:21 PM CDT, 4 hours 15 minutes before
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Local storm report, Aug 9, 8:15 PM CDT, 3 hours 21 minutes before
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</html>Local storm report, Aug 9, 8:19 PM CDT, 3 hours 17 minutes before
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</html>Local storm report, Aug 9, 8:35 PM CDT, 3 hours 1 minute before
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</html>Local storm report, Aug 9, 10:41 PM CDT, 55 minutes before
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</html>Local storm report, Aug 9, 11:04 PM CDT, 32 minutes before
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The site you requested is temporarily down for maintenance or an unexpected outage.
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Please try again in a few minutes.
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If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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</html>The office that day
Everything else NWS Chicago, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 8:41 PM CDT | Severe Thunderstorm Warning | LOT | Lee | 64 min |
| Aug 9, 9:09 PM CDT | Areal Flood Advisory | LOT | Lee | 4 hr |
| Aug 9, 9:39 PM CDT | Severe Thunderstorm Warning | LOT | Lee | 66 min |
| Aug 9, 9:49 PM CDT | Tornado Warning | LOT | Lee | 41 min |
| Aug 9, 10:10 PM CDT | Flash Flood Warning | LOT | Lee | 3 hr |
| Aug 9, 10:16 PM CDT | Areal Flood Advisory | LOT | DeKalb, LaSalle | 78 min |
| Aug 9, 10:23 PM CDT | Tornado Warning | LOT | Lee | 26 min |
| Aug 9, 10:49 PM CDT | Areal Flood Advisory | LOT | LaSalle | 45 min |
| Aug 9, 11:10 PM CDT | Special Marine Warning | LOT | 95 min | |
| Aug 9, 11:22 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Lake | 38 min |
| Aug 9, 11:22 PM CDT | Tornado Warning | LOT | LaSalle | 23 min |
| Aug 9, 11:23 PM CDT | Areal Flood Advisory | LOT | Grundy, Kendall, LaSalle, Livingston | 3 hr |
| Aug 9, 11:32 PM CDT | Areal Flood Advisory | LOT | DeKalb, LaSalle | 2 hr |
| Aug 9, 11:35 PM CDT | Severe Thunderstorm Warning | LOT | Grundy, LaSalle, Livingston | 70 min |
| Aug 9, 11:47 PM CDT | Flash Flood Warning | LOT | Grundy, LaSalle, Livingston | 3 hr |
| Aug 9, 11:54 PM CDT | Special Marine Warning | LOT | 96 min | |
| Aug 9, 11:59 PM CDT | Tornado Warning | LOT | Grundy, LaSalle | 17 min |
| Aug 10, 12:01 AM CDT | Flash Flood Warning | LOT | LaSalle | 2 hr |
| Aug 10, 12:36 AM CDT | Severe Thunderstorm Warning | LOT | Ford, Grundy, Iroquois, Kankakee, Livingston | 69 min |
| Aug 10, 12:39 AM CDT | Tornado Warning | LOT | Ford, Kankakee, Livingston | 36 min |
| Aug 10, 12:40 AM CDT | Special Marine Warning | LOT | 45 min | |
| Aug 10, 12:44 AM CDT | Areal Flood Advisory | LOT | Ford, Iroquois, Kankakee, Livingston | 2 hr |
| Aug 10, 12:54 AM CDT | Tornado Warning | LOT | Livingston | 36 min |
| Aug 10, 1:05 AM CDT | Areal Flood Advisory | LOT | Grundy, Kendall, LaSalle, Lee | 8 hr |
| Aug 10, 1:18 AM CDT | Flash Flood Warning | LOT | Ford, Kankakee, Livingston | 91 min |
| Aug 10, 1:20 AM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois | 55 min |
| Aug 10, 1:28 AM CDT | Tornado Warning | LOT | Iroquois | 16 min |
| Aug 10, 1:31 AM CDT | Tornado Warning | LOT | Ford, Livingston | 29 min |
| Aug 10, 1:42 AM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois, Livingston | 93 min |
| Aug 10, 1:52 AM CDT | Flash Flood Warning | LOT | Ford, Iroquois, Kankakee | 58 min |
| Aug 10, 1:56 AM CDT | Areal Flood Advisory | LOT | Ford, Iroquois, Livingston | 58 min |
| Aug 10, 2:32 AM CDT | Areal Flood Warning | LOT | Grundy, LaSalle, Livingston | 3 hr |
| Aug 10, 2:48 AM CDT | Areal Flood Advisory | LOT | Ford, Grundy, Iroquois, Kankakee, Livingston | 7 hr |
| Aug 9, 7:15 PM CDT | Areal Flood Advisory | LOT | Lake, Porter | 2 hr |
Nearby
Tornado Warnings in Illinois, 2026Every tornado warning in 2026Tornadoes 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.