Sioux Falls, S.D. (KELO-AM) - The National Weather Service reports the first measurable snow is on tap for the region beginning as early as Sunday night. Precipitation will develop later Sunday, gradually changing from rain or mixed precipitation over to snow from north to south. Snow accumulation is expected, especially near and north of Interstate 90 through Monday. At this time, potential for the greater snowfall, more than 4 inches, exists north of a Huron to Windom line. The heaviest snowfall will fall on Monday. Winds will increase substancially through Monday and may lead to significantly reduced visibilities through Monday night.