I live in Southern Minnesota. The precipitation has been truly extreme. One of the most noticeable signatures of climate change in our area is the increase in heavy precipitation events, and the wild pendulum swings between flood and drought. We have the wettest year-to-date on record, and I believe we're either at or pushing the wettest June (or any month!!) on record with a week in the month left to go. I know Sioux Falls, SD has had their wettest month ever already this June.
Luckily our soils around here have a lot of gravel underneath and are fairly well-drained. This is good for flood years. As long as the precipitation is spread out enough, only the most low-lying and poorly drained areas are flooded for more than a few hours. However, as all of this drains very rapidly into the upper groundwater then into our creeks and then rivers, the water level of the rivers can be pushed up quickly. Lots of local towns have been sandbagging along the river banks. This is the third time in four years that the Cannon River has had such major flooding, which had been considered a 1-in-100-year event up until this time.
I don't know about Sioux Falls, but near Aberdeen in Northeastern South Dakota, the soil has an impermeable layer of clay a few feet beneath the surface, so any rain above and beyond what can be absorbed by those first few feet of soil just sits on the surface. The terrain is incredibly flat and takes a long time to drain. If they had the precipitation we've had, they would be under feet of water. However they are much dryer than us here in Minnesota. There is a strong East/wet to West/dry gradient.
