Unprecedented: The Cause of Recent Iowa Flooding

Why Midwest Waters Are Rising: Understanding the Causes and Impacts 

According to the Associated Press: The recent surge in Midwest flooding can be attributed to relentless torrential rains. Sioux Falls, South Dakota, received a staggering 7 inches of rain over just three days, with neighboring areas like Canton seeing an unprecedented 18 inches. In Iowa, rainfall totals reached up to 15 inches since Friday alone. 

A series of intense rain events following one another throughout the month, exacerbated by atmospheric conditions in the Northeast directing storm paths over the Midwest coupled with a dominant high-pressure system in the East has slowed these storms down, intensifying the flooding. 

Compounding the issue is the already saturated ground from previous rainfall, limiting its ability to absorb new moisture and forcing excess water into rivers and streams. 

Understanding River Crests: Why They Matter Amid Flooding 

A crucial aspect of flood management is monitoring river crests—the highest water levels before receding—which are closely watched by forecasters. Recent downpours have caused rivers to swell rapidly, with crests either imminent or already reached in affected regions. 

In Sioux City, the Big Sioux River surged to a record-breaking 45 feet, prompting unprecedented challenges in flood prediction and response, according to Sioux City Fire Marshal Mark Aesoph. 

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Governor Kristi Noem of South Dakota reported that rivers like the James and Vermillion are expected to crest by Wednesday, noting that although flooding is widespread, strategic planning has helped mitigate its impact in populated areas. 

National Weather Service hydrologist Jeff Zogg predicts ongoing rainfall in northern Iowa, which will gradually flow southward over several days, eventually impacting major rivers like the Missouri and Mississippi. 

Climate Change's Role: Addressing the Growing Risk 

While flooding and heavy rains in June aren't new to the Midwest, attributing specific events to climate change remains complex. However, climate expert Shel Winkley notes that rising greenhouse gas levels contribute to warmer atmospheres capable of holding more water, intensifying rainfall, and increasing flood risks over time. 

As extremes become more frequent, communities must adapt to more frequent and severe flooding events, underscoring the need for proactive climate action and resilient infrastructure planning.