Alert archive / Illinois / Flash Flood Warnings in 2026
Flash Flood Warning 56, NWS Chicago, IL
NWS Chicago, IL issued this flash flood warning at Aug 21, 2026, 8:19 PM CDT for LaSalle County, Illinois. It was in force for 4 hr. 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 21, 2026, 8:19 PM CDT (01:19 UTC)
- Expired
- Aug 22, 2026, 12:00 AM CDT
- In force
- 4 hr
- Issued by
- NWS Chicago, IL
- Area
- Storm-based polygon
- Flood severity
- None
County LaSalle County, IL
The radar
The Chicago radar (KLOT), 73 km from the middle of the area, began a volume at 01:20 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 office that day
Everything else NWS Chicago, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 7:20 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 40 min |
| Aug 21, 7:58 PM CDT | Areal Flood Advisory | LOT | LaSalle | 4 hr |
| Aug 21, 9:10 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 19 min |
| Aug 21, 11:58 PM CDT | Areal Flood Advisory | LOT | LaSalle | 6 hr |
| Aug 22, 2:50 AM CDT | Small Craft Advisory | LOT | 31 hr |
Nearby
Flash Flood Warnings in Illinois, 2026Every flash flood warning 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; radar from the NEXRAD Level II archive.