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NOAA expects widespread river flooding this Spring

Southeastern Georgia included in prediction for minor flooding

This map depicts the locations where there is a greater than 50 percent chance of major, moderate or minor flooding during March through May, 2020.
This map depicts the locations where there is a greater than 50 percent chance of major, moderate or minor flooding during March through May, 2020.

JACKSONVILLE, Fla. – NOAA forecasters predict widespread flooding this spring, but do not expect it to be as severe or prolonged overall as the historic floods in 2019. Major to moderate flooding is likely in 23 states from the Northern Plains south to the Gulf Coast, with the most significant flood potential in parts of North Dakota, South Dakota and Minnesota.

For Southeastern Georgia, NOAA predicts minor river flooding. The likely culprits there would be the Altamaha River, which has been quite flooded for the past month. For Northeastern Florida NOAA does not predict Spring river flooding.

NOAA’s Climate Prediction Center is forecasting above-average temperatures across the country this spring, as well as above-average precipitation in the central and eastern U.S. Significant rainfall events could trigger flood conditions on top of already saturated soils.

“NOAA stands ready to provide timely and accurate forecasts and warnings throughout the spring,” said Neil Jacobs, Ph.D., acting NOAA administrator. “The dedicated employees of the National Weather Service continue to apply their skills and the latest technology to monitor additional rainfall, rising river levels, and the threat of severe weather to keep the public ahead of any weather hazard.”

Spring Flood Risk

Ongoing rainfall, highly-saturated soil and an enhanced likelihood for above-normal precipitation this spring contribute to the increased chances for flooding across the central and southeastern U.S. A risk of minor flooding exists across one-third of the country. The greatest risk for major and moderate flood conditions includes the upper and middle Mississippi River basins, the Missouri River basin and the Red River of the North. Moderate flooding is anticipated in the Ohio, Cumberland, Tennessee, and Missouri River basins, as well as the lower Mississippi River basin and its tributaries.

“Nearly every day, dangerous flooding occurs somewhere in the United States and widespread flooding is in the forecast for many states in the months ahead,” said Ed Clark, director of NOAA’s National Water Center in Tuscaloosa, Alabama. “Working with our partners across the National Weather Service we provide the best available forecast products to enhance resilience in communities at greatest risk.”

With soil moisture already at high levels across much of the central U.S., and many rivers running high in the central and eastern U.S., any heavy local rainfall could trigger flooding in these high-risk areas. The flood risk outlook is based on an integrated evaluation of a number of factors, including current conditions of snowpack, drought, soil moisture, frost depth, streamflow and precipitation.

“People depend on the National Weather Service’s river forecasts, and the accurate and timely streamflow data from more than 8,400 streamgages operated by the U.S. Geological Survey throughout the country play an integral part in making those forecasts,” said Bob Holmes, Jr., Ph.D, USGS National Flood Coordinator. "These streamgages report information like when streams have reached flood stage, or even when they break streamflow records. That kind of data allows the National Weather Service to bring the best science to bear for their forecasts."

The difference between Minor, Moderate, and Major flooding
The difference between Minor, Moderate, and Major flooding

Spring Outlook for Temperature, Precipitation and Drought

Above-average precipitation is favored from the Northern Plains, southward through the lower Mississippi Valley across to the East Coast. Large parts of Alaska are also likely to experience above-average precipitation in the months ahead.

Warmer-than-average temperatures are most likely from coast to coast with the greatest chances in northern Alaska, across the central Great Basin southward into the Gulf States, and into the Southeast and portions of the Mid-Atlantic. No part of the country is favored to experience below-average temperatures this spring.

Drought conditions are expected to persist and expand throughout California in the months ahead, and drought is likely to persist in the central and southern Rocky Mountains, the southern Plains, southern Texas, and portions of the Pacific Northwest.

NOAA produces seasonal outlooks to help communities prepare for weather and environmental conditions that are likely during the months ahead. Heavy rainfall at any time can lead to flooding, even in areas where overall risk is considered low. The latest information for a specific area, including official watches and warnings are available at http://water.weather.gov.

For information on flood insurance visit FloodSmart.gov and for information on what to do before, during and after a flood or other disasters, visit Ready.gov.


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