Increased Precipitation in South Dakota in Line With Climate Change Models

Jul 30, 2019

Credit National Weather Service

Seven months in to 2019 has seen near record levels of precipitation across South Dakota.  Officials say with more wet weather forecast it is likely a record-breaking year.  The increased precipitation is in line with existing climate models and experts see a trend supporting this idea.

Mike Gillispie is the service hydrologist for the National Weather Service in Sioux Falls. He says the southeast has seen the most extreme precipitation.

Gillispie says the region has received almost 27 inches of precipitation nearing the 1993 record of 28.71 inches between January and the end of July. He says while there have been cyclical patterns with temperature over the last century, precipitation remained consistent until around the early 90’s.

“Since the early 90’s – that’s the 92 – 93 type time period – the trend on the average precipitation has really increased.  We’ve gone from around 25 inches up to almost 30 inches now,” says Gillispie.

He says South Dakota has seen more extremes in precipitation with the three wettest and driest years on record occurring within the last 25 years.

Laura Edwards is the South Dakota state climatologist with SDSU Extension. She says as the climate warms the atmosphere can hold more moisture which creates the potential for more rain.

Edwards says many parts of the state have already exceeded the average precipitation seen most years. She says while this year has been extreme, there has been a general trend towards increased precipitation in the region.

“What we’ve seen in the trends in the last hundred years or so, is that the spring and fall seasons are getting wetter, faster, than the summer or winter seasons,” says Edwards.

Edwards says the trend is not the same everywhere.  She says the northern United States is getting much wetter while other regions, like the south west, are getting much drier.

Edwards says South Dakota is drier in the northwest and wetter in the southeast.  She says that pattern isn’t changing but it is getting wetter more quickly across the whole state. She says several years have had flooding over the last two decades and this year’s extreme moisture has compounded problems in parts of the state.