Chicago, IL

Weather Forecast Office

Spring Flood Outlook for Northeast Illinois and Northwest Indiana

Outlook Valid
Spring 2024 (March-May)

Last Updated
March 14, 2024

Based on current conditions, the risk of flooding during spring 2024 ranges from below average to near average in area river basins.

The spring flood outlook is updated each February and March. Next scheduled update is Spring 2025.

Risk Factors for Spring Flooding

To determine the relative risk of spring flooding, numerous factors are considered including snow cover, soil moisture, and current river conditions. A significant snow cover with high water content can increase the chances of flooding once warmer weather melts the snow. Elevated soil moisture conditions reduce the amount of rainfall that is soaked up by the ground and increase the amount of water that then runs off into area streams. Above average river levels reduce the river rise required to reach flood stage, while below average river levels would require an increased amount of river rise to reach flood stage.

Spring Flood Outlook 2024

Winter 2023-2024 Review

Fall 2023 Review

Spring Flood Risk Factors

Here is a general overview of spring flood risk factors across northeast Illinois and northwest Indiana river basins.

Risk Factor	Has effect on...	Current Condition	Effect on Flood Risk
Fall/Winter River Levels	Space in river for additional streamflow.	Near Average	No effect
Fall/Winter Soil Moisture	Space in soil for additional infiltration.	Below Average to Near Average	Decrease/No effect
Winter Precipitation	Snow cover, the amount of water available for spring melt.	Near Average	No effect
Winter Temperatures	Frost depth, the possibility that infiltration could be blocked by frozen ground.	Above Average	Decrease
Spring Precipitation	Amount of water headed to area rivers.	-	-
Spring Temperatures	Rate of melt for snow cover.	-	-

Valid March 14, 2024.

Current Snow Cover and Snow Water Equivalent

Modeled snow cover across area river basins was 0 inches in all areas.

Valid March 14, 2024. Click here for the latest snow cover information.

Current Soil Moisture and Frost Depth

Modeled soil moisture values across the area were generally near average to above average.

Frost depth is 0 inches across area river basins.

Valid March 14, 2024. Click here for the latest soil moisture information from the Climate Prediction Center.

Current River Conditions

River streamflow across the area is generally near average.

River ice spotters, river gauges, and satellite imagery indicate that no river ice exists on area rivers.

Valid March 14, 2024. Graphics update daily. Click here for the latest streamflow conditions from the USGS. Click here for the latest river ice spotter reports.

Spring Weather Outlook

The long term (next couple months) outlook from the Climate Prediction Center indicates above average temperatures likely over the first several weeks of March. There is a slight signal for above average precipitation during this period.

Although snow cover, soil moisture, and recent river levels can provide some indication of the relative risk of spring flooding, any weather system that produces heavy rainfall could cause flooding. Spring flood outlooks are not able to assess the risk of flooding due to heavy rainfall more than a week or so in advance.

Detailed Flood Outlook

Relative flood risk for river forecast locations can be viewed on the Advanced Hydrologic Prediction Service (AHPS) page for our area.

Temperature

Temperatures for winter 2023-2024 averaged about 5F to 9F above average in northeast Illinois and northwest Indiana. Despite one notable period of significant cold in January, the rest of winter was generally near average or above average.

Season-to-date temperatures were among the warmest on record for almost all areas.

December January February Temperature Anomaly

Precipitation

Precipitation for winter 2023-2024 averaged 0-3 inches above average in northern Illinois and northwest Indiana.

Snowfall

The first measurable snowfall (>0.1 inches) across northeast Illinois and northwest Indiana (right) occurred near average to slightly later than average, with a range from late October to early November for most areas.

The season-to-date snowfall ranged from about 8 inches to about 24 inches across area river basins, with the highest snow totals in southern Wisconsin and far northwestern Illinois. Observed snowfall was generally near average in northern Illinois and below average in northwestern Indiana and near the Lake Michigan shore.

River ice conditions which began in the middle of January caused multiple minor ice jams a at least one significant ice jam. Ice jam flooding occurred on the lower Kankakee River. Snowmelt and warming temperatures by late January and early February cleared rivers of ice.

Temperature

Temperatures were near to above average across northeast Illinois and northwest Indiana during fall 2023. Temperatures were 1-2F above average in far northern and northwestern Illinois, with others areas generally within 1F of average.

Precipitation

Precipitation was near average across northeast Illinois and northwest Indiana during fall 2023. Almost all areas were within 3 inches of the average.