Spring Flood Outlook #3 (released 3/13/25) 

Key Points

• The spring flood risk is below normal for the Mississippi River, and near to below normal for local tributary rivers across the NWS Quad Cities Hydrologic Service Area

• Most factors that contribute to flooding, including soil moisture, snowpack, and frost depth point to a decreased threat of spring flooding (see table below).

• Additional precipitation events in the upper Mississippi basin will be the main factor determining the severity of flooding this spring.

Details

Some factors contributing to the current decreased risk levels include: 

1. No snow on the ground and below normal precipitation throughout the local area and the headwater areas in Minnesota and Wisconsin.

2. Below normal soil moisture levels in the local area and across much of Minnesota and Wisconsin. 

3. Deep frozen soils remain upstream, especially near the headwaters of the Mississippi River. Little to no frost remains locally across the Quad Cities Hydrologic Service Area (HSA).

4. Near to below normal streamflow throughout the local forecast area and in most of the upper Mississippi River Basin. 

Through the spring, impacts from these factors are expected to change. One of the biggest factors that will drive any flood threat will be spring precipitation that we receive in the coming months, whether it be from rain or snow.  

Many factors are considered when determining the overall flood risk for the upcoming spring season.  The combination of these influences factor into the final determination. These factors are discussed in detail in the next few tabs and also in the Statistical Hydrological Outlook linked below.

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Use the links below to find the Graphical Probabilities and the Numerical Probabilities, respectively.
 

Graphical Hydrologic Outlooks	Spring Flood Risk One-Pager (PDF)   (Mar 13, 2025)	Statistical Hydrologic Outlook   (Mar 13, 2025)
Images below are examples which link to the Wapsipinicon River near DeWitt. Find all other locations in the Quad Cities Hydrologic Service Area in the drop down menu below.       Select Location: Mississippi River at Dubuque L&D 11Mississippi River at DubuqueMississippi River at Bellvue L&D 12Mississippi River at Fulton L&D 13Mississippi River at CamancheMississippi River at Le Claire L&D 14Mississippi River at Rock Island L&D 15Mississippi River at Illinois City L&D 16Mississippi River at MuscatineMississippi River at New Boston L&D 17Mississippi River at KeithsburgMississippi River at Gladstone L&D 18Mississippi River at BurlingtonMississippi River at Keokuk L&D 19Mississippi River at Gregory LandingMaquoketa River at ManchesterMaquoketa River at MaquoketaWapsipinicon River at IndependenceWapsipinicon River at AnamosaWapsipinicon River at De WittCedar River at VintonCedar River at Cedar RapidsCedar River at ConesvilleIowa River at MarengoIowa River at Iowa CityIowa River at Lone TreeIowa River at Columbus JunctionIowa River at WapelloIowa River at OakvilleEnglish River at KalonaSkunk River at SigourneySkunk River at AugustaDes Moines River at KeosauquaDes Moines River at St FrancisvilleFox River at WaylandPecatonica River at FreeportRock River at ComoRock River at JoslinRock River at MolineGreen River at GeneseoLa Moine River at Colmar   Go

Current/Forecast River Conditions

Current Conditions	Forecast Conditions	Long-Range Outlooks

Link To National Water Prediction Service (NWPS) and Additional River Forecast Resources

Flood Category Definitions

• Minor Flooding - minimal or no property damage, but possibly some public threat or inconvenience.
• Moderate Flooding - some inundation of structures and roads near streams. Some evacuations of people and/or transfer of property to higher elevations may be necessary.
• Major Flooding - extensive inundation of structures and both primary and secondary roads. Usually significant evacuations of people and/or transfer of property to higher elevations.  

What Are The Risk Factors For Flooding? 

Many factors are have been considered when determining the overall flood risk for the Spring, with the combination of these influences factoring into the final determination. These factors are discussed in detail below.

Seasonal Precipitation

Precipitation in eastern Iowa, northwest Illinois, and northeast Missouri has been below normal this winter. With that, much of the HSA, especially eastern Iowa and northwest Illinois, remains Abnormally Dry or in a Severe Drought due to below normal precipitation observed since the fall months in 2024. This is also reflected in soil moisture levels, which remain below normal. North of the area, precipitation in the upper Mississippi River Basin this winter has averaged below normal, aside from parts of far northern Minnesota, which are slightly above normal.

Latest outlooks from the Climate Prediction Center (CPC) favor near normal precipitation through the last half of March for all of the Upper Mississippi River Basin, with above normal precipitation favored for the month. Thus, guidance is highlighting the potential for an active month of weather. With dry soils and ongoing drought, any further precipitation should be allowed to infiltrate into the ground.  Although, for areas where frozen soils remain up north, much of the late winter and early spring precipitation will translate to runoff, rather than easily infiltrate.  

Below you will find the precipitation compared to normal in percentage. This graphic is courtesy of the High Plains Regional Climate Center.

River Conditions

Streamflow analysis from the United States Geological Survey (USGS) indicates the majority of the Upper Mississippi River watershed and tributary streamflows are near to below normal. Locally, we have seen streamflows near normal in Iowa and near to below normal in Illinois. Streamflows that are below normal levels would have more capacity to hold runoff from heavy spring rains.

Iowa	Illinois	Missouri

Soil Conditions

Given the continuation of below normal precipitation since the fall, soil moisture levels remain below normal. 
Latest analysis from the Climate Prediction Center shows soil moisture ranking profiles around 10-30% along 
east of the Mississippi River, with near normal soil conditions as we head towards the Mississippi headwaters. We
continue to see widespread Abnormally Dry to Severe Drought conditions through the Upper Mississippi
River Valley. Considering these factors, they favor a neutral to decreased threat for spring flooding, as drier soils 
will be better suited to soak in heavier rains once we lose the frost.

Snow Cover and Liquid Water Content

Recent above normal temperatures in the 1st half of March have melted all of the snow locally and most in the 
upper Mississippi River basin. This has resulted in decreased threat to Spring flooding. Any additional snow 
locally or upstream in the coming weeks, will have a minimal impact on Spring flooding for the remainder of the cold
season.

Current Snow Depth               Current Snow Water Equivalent

Images courtesy of the Midwest Regional Climate Center (MRCC) and National Operational Hydrologic Remote Sensing Center (NOHRSC)

Frost Depth

Recent above normal temperatures have resulted in losing most if not all of frost in the ground across 
Iowa, Illinois, and Missouri. Upstream across Minnesota and Wisconsin, deep frost depths over 20
inches remain. Any precipitation that falls upstream on top of this frozen ground will increase runoff 
into the mainstem Mississippi resulting in a neutral threat to Spring flooding.

Frost Depths - North Central River Forecast Center

Regional Frost Depths as of March 13, 2025

Ice Jam Flooding

Temperatures have been quite variable this winter, with stretches of cold resulting in plenty of river ice. 
The recent stretch of warm weather has allowed for most of this ice to melt and/or breakup.
Current observations are indicating a low-medium threat for break up ice jams, but fortunately we are lacking 
any heavy rain at the moment. This should mean that the ice can gradually melt/break up without many impacts. 
Will continue to message a Neutral to Decreased Threat for ice jam flooding this Spring.

River and Streamflow Information:

• National Weather Service: water.weather.gov
• US Geological Survey: water.usgs.gov/waterwatch
• Corps of Engineers: rivergages.com 

Flood safety and flood insurance information:

• NWS Flood Safety: www.floodsafety.noaa.gov
• National Flood Insurance Program: www.floodsmart.gov

Precipitation, temperature, and soil moisture information:

• National Operational Hydrologic Remote Sensing Center: www.nohrsc.noaa.gov
• NWS Graphical 7-Day Forecast: https://graphical.weather.gov/sectors/uppermissvly.php
• NWS Climate Prediction Center: www.cpc.ncep.noaa.gov
• US Drought Portal: www.drought.gov 

Questions or Comments

If you have questions or comments about this spring flood and water resource outlook please contact:

National Weather Service Quad Cities Hydrology Team
9040 Harrison St
Davenport, IA 52806
Email: cr.dvn-hydro@noaa.gov