Atmospheric River That Could Spark 1-in-1,000-Year Flood Shifts Paths

The atmospheric river currently fueling deadly U.S. storms across the Midwest and South is shifting northwest later this week, meteorologists warned.

Why It Matters

Earlier this week, AccuWeather meteorologists warned of a 1-in-1,000-year flood posing threats to several states. An AccuWeather spokesperson told Newsweek that floods like this have a 0.1 percent chance of happening in any given year.

Myriad weather alerts and warnings remain in place across the U.S. from eastern Texas northeast through Ohio on Thursday. Meteorologists are warning of floods, severe storms and strong winds.

On Wednesday, the storms fueled tornadoes and heavy rainfall across multiple states, killing at least one person, The Associated Press reported.

What To Know

The heavy rounds of rainfall and strong winds are from an atmospheric river, AccuWeather reported.

Atmospheric rivers are a “long, narrow region in the atmosphere—like rivers in the sky—that transport most of the water vapor outside of the tropics,” according to the National Oceanic and Atmospheric Administration.

The storms brought by atmospheric rivers are known for their heavy snow, heavy rain and strong winds. They more commonly affect the West Coast, particularly during the winter months.

Severe flood risk remains for numerous states throughout the rest of the week, and the National Weather Service (NWS) Weather Prediction Center warned that the storm’s focus will shift northwest later this week to impact the middle Mississippi Valley southwest through the Arkansas-Louisiana-Texas region.

States at the highest risk of significant floods on Wednesday night and early Thursday morning were western Tennessee and western Kentucky, but National Water Center service coordination hydrologist Jason Elliott told Newsweek that the area of greatest impact will shift to Arkansas, Missouri, southern Indiana and southern Illinois by Friday, before returning to western Tennessee and western Kentucky by Saturday.

What People Are Saying

NWS Weather Prediction Center in a forecast: “A high risk of excessive rainfall (level 4/4) is in effect Thursday from southwestern Kentucky into western Tennessee and northeastern Arkansas where the greatest threat for numerous instances of life-threatening flash flooding exists following heavy rainfall over the same areas Wednesday.”

The forecast added: “A broader moderate risk (level 3/4) stretches from the Lower Ohio Valley southwest through the Mid-South with a slight risk (level 2/4) across the broader Ohio Valley southwest to the ArkLaTex where additional scattered to numerous instances of flash flooding are possible.

“Another moderate risk is in effect on Friday with the focus shifting a bit northwestward over the Middle Mississippi Valley southwest through the ArkLaTex, areas that have not been as hard hit compared to the Lower Ohio Valley/Mid-South, but are still expected to see significant heavy rainfall totals and scattered to numerous instances of flash flooding.”

What Happens Next

Rounds of heavy rainfall, severe thunderstorms and strong winds will continue across a large swathe of the U.S. through Saturday night. Any flooding that occurs, particularly of major rivers, could persist until early next week.