DES MOINES, Iowa (AP) -- A strong winter storm made its way across the Upper Midwest Tuesday, creating treacherous travel conditions, spurring warnings urging people to stay off the roads and closing coronavirus testing sites.
The National Weather Service issued winter storm warnings for parts of Nebraska, Iowa, Kansas, Missouri, South Dakota, Wisconsin and Illinois.
Snow was so heavy in western Nebraska Tuesday morning that Interstates 80 and 76 were closed for several hours in both directions after numerous accidents, and the Nebraska Department of Transportation warned people to avoid unnecessary travel.
By 4 p.m. Tuesday, the storm had mostly moved out of Nebraska. The Nebraska State Patrol said troopers responded to more than 150 weather-related incidents, including 129 motorist assists.
Many government buildings and properties closed ahead of the storm, including COVID-19 testing sites in Norfolk, O'Neill, Nebraska City, Beatrice, Bassett and Auburn. Planned testing sites in Nebraska City, Cozad, York and Valentine will not open Wednesday. State officials urged Nebraskans to continue registering for testing, which is expected to resume Thursday.
Police in Omaha reported several accidents blamed on slick roads. Unofficial snowfall amounts by afternoon included about 6.5 inches (16.5 centimeters) in Lincoln and Omaha, 7.5 inches (19 centimeters) near Nebraska City, 7 inches (18 centimeters) in Wayne and 2 inches (5 centimeters) to 5 inches (13 centimeters) in central Nebraska.
Heavy snowfall of up to a foot (30 centimeters), and perhaps more in some spots, was forecast in parts of Iowa, where the state Department of Transportation urged people to delay travel plans. The department's road conditions map showed most highways in the western part of the state covered or partly covered with snow by midday Tuesday.
"Travel conditions are likely to go downhill all day/night," the Iowa department said on Twitter. "If you must travel in the impacted areas, buckle up, slow down and allow plenty of space between vehicles."
Earlier Tuesday, snowfall was heavy, causing visibility problems for motorists and rapidly deteriorating road conditions, Iowa State Patrol spokesman Sgt. Alex Dinkla said. He added that crashes were happening across the state with heavy post-Christmas travel.
"All our troopers are very busy right now covering crashes all over Iowa. Road conditions are very dangerous," he said.
The city of Des Moines had more than 200 employees from public works, parks and recreation, and wastewater reclamation departments on snow removal duty. Public Works Director Jonathan Gano said 100 snow plows, trucks and other equipment were activated to 24-hour operation until the snow stops.
"We're looking at 8 inches followed by some ice so that's going to be a wonderful complication and I think I've seen the forecast for Jan. 1 which has another 4 to 5 inches," he said.
Wisconsin was also bracing for up to 10 inches (25 centimeters) of snow in some areas. The forecast called for 3 to 6 inches of snow in the Milwaukee area.
AccuWeather said parts of southeast Nebraska, northeast Kansas, northern Missouri and southern Iowa could see ice accumulations of up to a quarter of an inch, which could weigh down power lines and branches and cause power outages.
In Topeka, morning snow gave way to freezing rain and then rain as the temperature moved east. In the Kansas City area, light snow on Tuesday morning resulted in several accidents. Among them were several rollover wrecks on the Kansas side of the metropolitan area.
The storm had mostly moved northeast out of Missouri by late Tuesday afternoon.
The Missouri Department of Transportation said roads were mostly or partly covered with snow in the northern third of the state. But the department added late Tuesday afternoon that all roads in the central region of the state had been cleared.
Forecasts showed the storm would move into the Southern Plains later in the week, when parts of Texas and Oklahoma could receive snow or a wintry mix Wednesday and Thursday. Texas Gov. Greg Abbott on Monday placed several state agencies on standby.