Above-average Precipitation, Flood Risk Predicted for Indiana this Spring

NOAA’s 2020 spring outlook forecasts widespread flooding and rain, but at levels below 2019’s historic season.
March 27, 2020

In what may come as a small relief to farmers and Hoosiers living near waterways, forecasters say this year’s spring rainfall will most likely be above-average but not as severe or prolonged as 2019’s record-setting season.

The National Oceanic and Atmospheric Administration’s Spring Outlook forecasts the entire state of Indiana has a higher than 50% chance of above-normal amounts of precipitation.

The entire state is also projected to face at least a greater than 50% chance of some flooding, with some parts of the Wabash, White and Patoka River basins in southwest Indiana facing moderate levels of flooding.

Spring outlook
The NOAA's spring outlook projects the entire state of Indiana has a higher than 50% chance of above-normal amounts of precipitation.

“Last year, we experienced widespread historic flooding across much of the U.S., and nearly 165 million people were impacted by that flooding. Flooding continues to be a factor for many Americans this spring,” said Mary Erickson, deputy director of the National Weather Service.

Heavy rainfall has already claimed the lives of six people in the state this year, including a mother and her three children who drowned after their vehicle was swept away by flooding in Laurel, about 60 miles southeast of Indianapolis.

The NOAA said highly saturated soil conditions from above-normal precipitation over the fall and winter months can induce flooding with more heavy rainfall events.

NOAA flood map
The entire state of Indiana has a greater than 50% chance of experiencing at least minor flooding.

The U.S. Geological Survey said its stream gauges were observing significantly higher-than-normal conditions for this time of year.

“Since this past October, USGS has measured water levels exceeding flood stages at over 1,100 locations covering most of the eastern half of the United States. And, so far this calendar year, we have already had 28 of our long-term stream gauges report periods of record peaks,” said USGS national flood coordinator Bob Holmes.

Stream gauges along parts of the Wabash River bordering Illinois, the White River, Patoka River and Whitewater River have already shown above normal stream flows.

The gauges with the highest readings are in south and southwestern Indiana near Bedford, Shoals, Petersburg, Winslow and Princeton.

USGS streamflow readings
USGS streamflow monitoring for Indiana

The above-normal precipitation projected for spring could greatly affect the state’s agricultural industry, just like it did in 2019.

The NOAA found that the 12-month period between July 2018 and June 2019 was the wettest ever recorded.

During that period of time, heavy rainfall affected central and southern Indiana and Lake Michigan, causing flooding in waterways that flow through those regions.

The water levels in Lake Michigan have continued to rise, necessitating an executive order from Indiana Gov. Eric Holcomb that directs state agencies to do everything in their power to help lakeshore residents track water levels and prepare for floods.

Indiana annual crop summary
Heavy rainfall in spring 2019 limited the total corn acreage harvested for grain to the lowest total since 1983.

The heavy rainfall last year also limited the total corn acreage harvested for grain to 4.82 million acres, the lowest total since 1983.

“Last spring, we had a lot of frequent rainfall that simply prevented farmers from doing the field work and the planting necessary to get the crop in last year, so it ended up being, at least for Indiana, one of the latest planting seasons in the past 40 years,” said Bob Nielsen, extension agronomist at Purdue University.

The late planting season puts added stress on the supply chain that farmers depend on and the farmers themselves.

Nielsen said farmers were lucky they experienced a mild August, which allowed the state’s corn crops to flower and mature before a killing frost had a chance to destroy them.

“It ended up being a really late planting season, however yields statewide ended up being remarkably good considering how late the crop was put in the ground,” said Nielsen. “So, I think to a large degree, we could say we dodged a bullet.”

Nielsen said long-term forecasts are not known for their reliability, but the amount of rain that has fallen around the state this year could lead to another late planting season.

“There’s not been a lot of opportunity for any spring tillage work or fertilizer application, because it’s been too wet,” he said. “So that sort of begins the domino effect. If you delay tillage and you delay fertilizer and delay herbicide, that naturally delays planting.

According to Nielsen, who has studied corn and agronomy for nearly four decades, all farmers can do is ensure they are ready to move once the soil is ready for planting.

“Because our climate is obviously becoming more variable one year to another, and we’re getting these extremes more often than we used to, it just comes down to good common sense and sound agronomics,” said Nielsen. “Since we can’t predict the weather very accurately, there’s not much you can plan with confidence ahead of time. You just have to be ready to react to whatever Mother Nature throws at you.”

Above-average Precipitation, Flood Risk Predicted for Indiana this Spring