South Dakota is in the midst of its wettest year on record and Mitchell has seen its third-wettest year after historic spring and summer rains swamped fields and flooded cities, roads and homes throughout the state.
“I think the story of the year is precipitation,” said Laura Edwards, state climatologist for South Dakota. “Statewide we already have the wettest season on record, and we still have five or six weeks to go. That doesn’t even count November.”
Edwards said South Dakota has received a statewide average of 29.37 inches of precipitation so far this year. The previous wettest season in the state was in 1915, when 27.97 inches of precipitation fell.
Weather statistics from the National Oceanic and Atmospheric Administration indicate the Mitchell area has received 34.09 inches of precipitation so far in 2019, which already ranks it as the third-wettest year for the area. The highest amount of precipitation recorded in Mitchell for a full year was in 1993, when the area received 36.19 inches of precipitation, and in 1908, when 36.14 inches of precipitation was recorded.
Edwards said the heavy rains in the southeastern portion of the state contributed heavily to the overall state record for precipitation.
“That whole southeastern region was very wet in September. But it was just constantly wet all season long,” Edwards said.
Mitchell received its fair share of moisture in September, as well. Reports indicate the community saw 7.63 inches of precipitation during the month, the highest total for a September in the last 20 years. The 2.78 inches that fell in March is also the highest for the month since 1999.
Every month so far in 2019, with the exception of January with 0.54 inches, has seen more than an inch of precipitation. Weather statistics indicate Mitchell received 1.09 inches in February, 3.16 inches in April, 4.26 inches in May, 2.63 inches in June, 6.46 inches in July, 4.13 inches in August and 1.33 inches in October.
Some of the most destructive rains fell in July, when a number of heavy storms passed through the area, pushing rivers out of their banks and stopping the crop growing season in its tracks. The summer rainfall, compounded with earlier spring rains and the runoff from melting snow, pushed the Mitchell area into historic flooding territory.
The rains wrecked havoc on the planting season for farmers in the area. Mike Miller, who farms outside Freeman, said he didn't get nearly all of his land planted this spring. He also raises cattle, and wet conditions are a notoriously bad condition for calving season.
"I got maybe 50 percent of my ground planted this year, and calving season was just a nightmare," Miller said.
A longtime farmer, Miller said this year surpasses previous years in terms of the impact it had on his operation. He said 1993 and 1995 were two years that he recalled being similar to this year in terms of precipitation, but 2019 has been one for the record books.
"Those two years stick out with me that were incredibly wet. And this year just seemed to be worse by a factor of 10. It started in the middle of April and didn't let up until the beginning of October," Miller said.
What crops he did get in the field did well and brought excellent yields, assuming the mid-summer rains didn't drown out what he managed to get in the ground. He also managed to cut his silage at the right time and avoided having to bring heavy trucks into the saturated fields.
But Miller said he and other farmers are hoping for better conditions to start 2020.
"I just want to get the year finished up and and behind me, then start again next year. It can't be worse, right?" Miller said.
Rivers took in a lot of runoff from the snow melt and the rains that followed in the spring and summer, Edwards said. She said the James River, Big Sioux and Missouri rivers received 16 times the average amount of runoff they usually get during the month of September, which she estimated was double the previous record.
“That’s exceptional,” Edwards said.
The United States Army Corps of Engineers announced this week that it was incrementally increasing releases from the Jamestown and Pipestem dams in North Dakota as the cities of Jamestown and LaMoure in that state prepare for higher flows. The combined releases were expected to reach 2,200 cubic feet per second by Friday. That release will allow the dams to evacuate as much flood storage as possible prior to spring runoff. The combined releases are expected to be scaled back to 1,400 cubic feet per second by Dec. 1.
Scott Dummer, development and operations hydrologist for the Missouri River Basin Forecast Center in Pleasant Hill, Missouri, said the heavy rains and saturated soil in South Dakota contributed greatly to the runoff that is affecting the entire river system.
“Since the soil was very saturated, any rainfall that was adding to more runoff as compared to what we’d see if the soil were drier,” Dummer said. “That’s the prairie pothole region in the Dakotas, and a lot of sloughs and that kind of thing are filled up. Any precipitation or melting snow or rain is going to cause more runoff.”
Dummer said dam releases by the Corps of Engineers are up this year due to the amount of rain South Dakota and North Dakota received.
“Since it’s been so wet they’ve been releasing more than normal to try to remove that water out of those reservoirs,” Dummer said.
Edwards said she didn’t expect the increased releases to strongly affect residents farther downstream.
“By the time it gets down to (the Mitchell region), it won’t be that big. Their objective is to move water down the system before it freezes in, as that limits what they can do with releases,” Edwards said.
Unfortunately, the long-term outlook for drier conditions is not good. Edwards said a combination of soil saturation and a forecast that indicates more moisture is on the way may mean those in the Mitchell area and across the state could be dealing with wet conditions for the foreseeable future. The months between December and April will be telling on how the situation will play out in the spring and summer, she said.
“For the winter and spring, the odds are favoring wetter than average conditions," she said. "It’s pretty consistent the last couple of months with computer models and forecaster discussions and there’s fair confidence of having another wet spring and some flooding issues."
In fact, conditions appear very similar to this time last year, she said. But in any case, the area has taken about as much moisture as it can.
“Last year at this time was very similar. We’ve seen this in a number of recent years with wet falls and very wet springs,” Edwards said. “(Forecasts are) showing December through April in general as wetter than average. I’m not saying it will be as big a snow year as it was last year. It’s hard to see that much snow two years in a row, and it’s not what we need. But even with an average winter, we’re going to see some issues. Our soil is very wet and there’s a lot of water on land.”