Spring Flooding Outlook- 2024
The 2024 National Hydrologic Assessment offers an analysis of flood risk, water supply, and ice breakup and ice jam flooding for spring 2024 based on late summer, fall, and winter precipitation, frost depth, soil saturation levels, snowpack, current streamflow, and projected spring weather. NOAA’s network of 122 Weather Forecast Offices, 13 River Forecast Centers, National Water Center, and other national centers nationwide assess this risk, summarized here at the national scale. Click here for more information from the National Weather Service.
This spring season, approximately 122 million people are at risk for flooding in their communities, with nearly 350,000 at risk for moderate flooding. No major flooding is expected this spring.
Above normal temperatures, combined with well below average snowpack over the Northern Plains, Midwest, and Ohio Valley, will significantly reduce the flood risk over much of the United States this spring. Moderate flooding is expected over tributaries to the Lower Missouri River in Kansas and Missouri, as well as tributaries to the Lower Arkansas River in Kansas and Oklahoma. Minor to moderate flooding will be possible over much of the southern United States due to typical spring rainfall. Above normal snowpack in northern Nevada and southern Idaho will lead to the potential for minor flooding for higher elevation basins in those areas.
Current water supply forecasts in the western United States indicate normal water supply conditions over California, Nevada, and the Great Basin due to above average snowpack. Over the Northwest, as well as the Colorado, Upper Missouri, Arkansas, and Rio Grande basins, normal to below normal water supply volumes are expected due to a near to below normal snowpack. Longer term water supply issues are possible this summer and fall in the Greater Mississippi River Basin and portions of Texas due to the lack of winter precipitation and expected precipitation patterns through the remainder of spring and into the fall.
In Alaska, spring ice breakup and snowmelt flood potential is forecasted to be normal for the majority of the state, with the exception of portions of the Copper River Basin due to above normal snowpack.
Based on the expected spring flood outlook, average hypoxia zones are expected for the Gulf of Mexico and for Chesapeake Bay.
Heavy Rainfall and Flooding
The information presented in this report focuses on spring flood potential, using evaluation methods analyzed on the timescale of weeks to months, not days or hours. Heavy rainfall at any time can lead to flooding, even in areas where the overall risk is considered low. Rainfall intensity and location can only be accurately forecast days in the future; therefore, flood risk can change rapidly. Stay current with flood risk in your area with the latest official watches and warnings at weather.gov For detailed hydrologic conditions and forecasts, go to water.weather.gov.
