Sections of southwestern, central, and far southeastern South Dakota are under a winter storm warning through Friday. A portion of north central and southeastern South Dakota is under a winter weather advisory.
Melissa Smith with the National Weather Service in Rapid City says fog moved through her forecast area earlier Thursday, creating moisture in the atmosphere.
She says rain showers will eventually transition to snow later this evening, with widespread accumulations expected through tomorrow.
"With the snow picking up during the morning hours, some snowfall amounts that we're seeing are probably going to range from 4-8 inches across a large portion of western South Dakota, mainly to the south of I-90. And, we could even see some areas get up to a foot of snow in a pretty short period of time, within 24 hours or so," Smith says.
Smith says this fast-moving system also is expected to have another component.
"The other thing that we're looking at is ahead of this snow, before things change over to snow, we are looking for the potential for some ice, especially as you get into south central South Dakota, maybe just west of the Missouri River or so -- out on the South Dakota plains. It's not going to change over to snow as quickly [there], so we're looking at probably some freezing rain and freezing drizzle to linger over that area a little bit longer tonight and into tomorrow morning. Which then will cause maybe some ice accumulation of maybe a tenth to a quarter of an inch," Smith says.
She says hazardous travel is expected on Friday. Smith says it's important for motorists to have a winter survival kit if they must travel.
As the storm moves away, Smith says Saturday will provide better conditions for driving.