CHICAGO — Rain and rapidly rising temperatures accompanied by thick fog threatened to cause flooding Saturday in the Midwest after days of Arctic cold, heavy snow and ice.
Thick ice on roads that contributed to dozens of deaths had thawed and mountains of snow turned into pools and streams of water.
The National Weather Service posted flood watches and warnings Saturday for parts of Illinois, Iowa, Wisconsin, Indiana, Michigan and Missouri. As much as 2 inches of rain fell in two hours during the night in west-central Illinois, the National Weather Service reported Saturday.
And as warm air collided with cold, the weather service posted tornado watches for parts of Oklahoma, Arkansas, Missouri, Illinois and Kansas.
After subzero temperatures in places earlier in the week, Saturday morning readings were in the 40s as far north as Cheboygan, Mich., at the top of the state’s Lower Peninsula, the weather service said. However, up to 7 inches of snow is possible in the state Sunday, the agency said.
The weather service said the Chariton River was overflowing and causing minor flooding in Chariton, Iowa. Flood stage is 15 feet; the river was at 16.6 feet at 3 a.m. Saturday and expected to rise a bit more. It said road flooding was reported in parts of Missouri.
Around Chicago, Cook County authorities offered sandbags to communities that needed to fortify low-lying areas, county spokesman Sean Howard said.
Temperatures also were rising in the Pacific Northwest, which has been pummeled by deep snow.
In Portland a couple inches of rain through Saturday was expected to wash away much of the 19 inches of snow that by one measurement had made December the city’s snowiest month since January 1950.
“Once we start to see rain, it’ll really melt down,” weather service meteorologist Charles Dalton said.