Spring is the season of new beginnings! With this shift in Earth’s tilt comes warmer temperatures and higher rainfall resulting in melting snow flowing downstream into rivers, and potentially our communities. On March 19, the National Weather Service released the 2020 Spring Flood Outlook. As a comprehensive snapshot of flood risk and water supply across the country, the Spring Flood Outlook includes the National Hydrologic Assessment produced by the Water Prediction Operations Division of the Office of Water Prediction at the National Water Center in Tuscaloosa, Alabama.
The National Hydrologic Assessment is not a one-person job and is developed collaboratively by a team across NOAA’s national network of 122 weather forecast offices, 13 river forecast centers and other national centers. As a hub for collaboration to improve water resources forecasting, the National Water Center has served as the lead for this effort since 2018.
The analysis which results in the Spring Flood Outlook map includes information about the late summer and fall precipitation levels from the previous year, current conditions of frost depth, soil saturation levels, streamflow and snowpack, and future prediction for temperature, precipitation and rate of snowmelt.
The assessment identifies areas that are expected to see a greater than 50% likelihood of exceeding minor, moderate or major flood levels.
Minor flooding usually causes minimal or no property damage to individuals. However, it can offer some public threat via inundation (flooding) of roads.
Moderate flooding is usually accompanied by some inundation of structures and roads near streams. Some people may need to be evacuated, and some property or resources many need to be moved to higher ground to avoid being submerged in water.
Major flooding will likely result in extensive inundation of structures and roads. A considerable number of people may need to be evacuated, and a significant amount of property and resources may need to be evacuated to higher ground.
These types of flooding relate to the amount of water likely and the kinds of risk or potential impacts of the flooding. This information is important because it allows individuals, businesses and any water-sensitive sector to take precautions and prepare for possible upcoming conditions.
This year’s Spring Flood Outlook showed that heavy rainfall in mid-February and early March brought moderate to major flooding across much of the middle to lower Mississippi River basins and the Southeast.
The streamflows and soil moisture conditions were well above normal, which enhances the risk of flooding from storms typical of the spring season. These conditions suggest that rivers in the Lower Mississippi Basin and parts of the Lower Missouri River Basin could exceed moderate flood levels from March through May this year.
Why is this information Important?
Flood forecasts like the Spring Flood Outlook provide information that allows communities, individuals and businesses to prepare for the possibility of future flooding and take steps to minimize impacts.
Flooding can cause damage to homes and businesses, as well as essential community infrastructure like bridges, roadways, sewer systems, drinking water treatment facilities and power generation plants. In addition, floodwaters can carry waterborne diseases and potentially interfere with the tourism industry and agricultural production.
The most critical concern is risk to human safety and the possible loss of lives. According to the National Weather Service, floods are the most common and costly natural disaster in the United States. Flooding is a threat to some part of the United States and its territories nearly every day.
Forecasts allow communities time to take advanced actions like preparing plans for community evacuations or making alterations to infrastructure, such as elevating critical equipment above floodwaters.
Individuals and families can also prepare well in advance of danger. Critical actions include creating a communications plan so that family and friends know how to get ahold of each other. People can make and maintain an emergency kit that includes enough food, water and medicine for everyone in the home for at least three days. If possible, include extra batteries, clothes, blankets and a battery-operated radio.
It is also important to know your risk. Is your home or business in a floodplain? Are there places along the roads that you normally travel that are likely to collect water and flood? If flooding occurs, where will you go, and what is the best route to get there?
Always remember that floods do not wait for forecasts! Some floods develop slowly, while others develop in just a few minutes — unexpectedly. It’s important to stay aware of changing conditions and know what to do if you find yourself in a flood.
Always obey evacuation orders and avoid floodwaters. Do not walk through moving water, just 6 inches of moving water can knock an adult off their feet. And never drive into flooded areas. If you come upon a barricade or flooded road, turn around, don’t drown. You never know how deep the water is or if the road has been washed away or compromised beneath the water. It’s not worth the risk.
Please take the risk of floods this spring seriously and keep in mind a few simple steps can greatly minimize how much a flood affects you.
For additional information please see the following sites:
- The 2020 Spring Flood Outlook.
- Story Map for the 2020 Spring Flood Outlook.
- Stay current with flood risk in your area with the latest official watches and warnings.
- For flood safety tips and resources: https://www.weather.gov/safety/flood, https://www.ready.gov/floods.
Meet the author
Karen Bareford, Ph.D.
Sea Grant Water Resources Lead
Karen Bareford works with the Alabama Water Institute, the University of Alabama and the National Sea Grant College Program. She provides leadership on water recsource initiatives and efforts... Read more
Phone: 205-348-9719
Email: [email protected]