SIOUX FALLS, SD (KELO) -- Monday featured a noticeable split along the Missouri River, with below average temperatures East River and near/above average highs being observed out west. As of 2 pm CST Monday This split will linger as we head into the night with a little disturbance moving into KELOLAND. Out west, and to a lesser extent in south-central KELOLAND, we'll have cloud cover in place to insulate the surface...keeping lows above zero. Where we have clearer skies, however, temperatures are expected to plunge below zero and by a good margin at times. Please keep this in mind as you get ready for work and school on Tuesday. Overnight into Tuesday will be another cold stretch East River, with "milder" temperatures West River and a few snow showers along the way. Less than an inch of accumulation is expected out of that outside of the Black Hills. Speaking of the hills, a winter weather advisory remains in effect until 11 am MST Tuesday. 3-6" of snow is possible into Tuesday with some locally higher amounts possible. The second half of the work and school week will feature a noticeable January thaw that blankets KELOLAND with 30s and even 40s at times through Friday. Enjoy these temperatures as they come along, because a deeper blast of Arctic air is on the way for the weekend and into the start of next week. Single-digit highs are likely by next Sunday and Monday, with lows well below zero. What's incredible to think about is how cold it will be with little to no snow on the ground in many areas. With a fresh blanket of snow, it would be even colder. Here's a look at your extended forecast: