Record-breaking rain across Texas and Oklahoma this week caused widespread flooding, the likes of which the region has rarely, if ever, seen. For seven locations there, May 2015 has seen the most rain of any month ever recorded, with five days to go and the rain still coming. While rainfall in the region is consistent with the emerging El Niño, theMore
Major flooding continues in parts of the Upper Midwest this week. It’s the result of heavy rain that fell over the past couple weeks in Iowa, Minnesota, and Wisconsin. Now all that water is slowly working downstream from the tributaries of the Mississippi River into the river itself.
In Iowa, the Cedar River is slowly receding, but river gauges at Cedar Rapids and Waterloo both had their second highest crest on record. Major flooding is expected this weekend along the Mississippi River along the Iowa-Illinois border, with moderate flooding downstream in northern Missouri.
Heavy rain across the upper portion of the Mississippi’s watershed is the main driver of the flooding.
Over the course of 24 hours last week, a broad area of the Mississippi River watershed had more than 3 inches of rain, and a few locations received more than 6 inches. But over the course of two weeks, some of those same locations totaled more than 10 inches of rain.
Eric Sorensen, a meteorologist at WQAD in Iowa, looked up the top 10 floods in Cedar Rapids since the 1850s and found that five of those have happened since 1993. This may not be so surprising, as a recent Climate Central analysis of more than 3,000 rain gauges across the U.S. indicates that all but two of the Lower 48 states have seen an increase in the number of heavy downpours happening each year, on average, compared to the 1950s.
This is consistent with the research results from the National Climate Assessment, which shows that the Upper Midwest has had a 37 percent increase in the amount of intense precipitation falling in the heaviest events between 1958 and 2012.
While climate change did not necessarily cause this or any other particular flood, the warming atmosphere and increase in heavy downpours makes floods of this magnitude more likely than in past decades.
As the planet warms, the amount of evaporation increases. That means when storms form, they have more water available for precipitation, increasing the likelihood of this type of flood and with it, the risks to more life and property in the future.