Mississippi River at Thebes, IL
River level and flood forecast · Alexander County
Normal21.3 ftas of Mon 3 PM
The river is 11.7 ft below flood stage (33 ft).
Flow: 262,000 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Sun, Dec 31, 6 PM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 42 ft |
| Moderate flood stage | 37 ft |
| Flood stage | 33 ft |
| Action stage | 30 ft |
| Record crest (January 2, 2016) | 47.74 ft |
What floods at each level
From the National Weather Service, highest first.
- 34 ftThe town of Thebes begins to flood.
- 33 ftThe town of Gale begins to flood.
Highest crests on record
- 47.74 ft — January 2, 2016
- 45.91 ft — May 23, 1995
- 45.52 ft — May 3, 2011
- 45.51 ft — August 7, 1993
- 45.15 ft — July 4, 1844
Recent crests: 34.28 ft (April 9, 2025) · 33.43 ft (July 19, 2024) · 35.77 ft (July 12, 2024) · 34.66 ft (May 12, 2024) · 33.14 ft (May 4, 2024)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (THBI2); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.