With nightfall, blowing snow and open countryside, visibilities could drop below a half mile tonight, according to the National Weather Service.

Visibility on south Minnesota Ave.tonight between Sioux Falls and Harrisburg and west of Harrisburg on Lincoln County 110 was in the quarter to half mile range around 5:15 p.m. Saturday evening.

The Sioux Empire is under a wind chill advisory, with gusts up to 45 mph from the northwest and wind chills in the -20 to -35 range expected. The NWS says the immediate Sioux Falls area may get up to an inch of snow Saturday evening.

Lincoln County 110 on west side of Harrisburg, S.D., 5:15 p.m. Saturday, Jan. 3, 2015, showing poor visibility conditions. Photo by Todd Epp.