Intense fall storm hits Midwest, dumping heavy snow in western SD, spawning tornado in Neb.

This NOAA satellite image taken Thursday, October 03, 2013 at 11:00 AM EDT shows a developing storm in the Northern Rockies is generating clouds with rain showers and snow across the Upper Mississippi Valley and Northern and Central Plains into the Northern Rockies and Intermountain West. Fair conditions exist across the remaining regions. (AP PHOTO/WEATHER UNDERGROUND) (The Associated Press)

SIOUX FALLS, S.D. – Strong storms are moving into the Midwest, dumping heavy snow in South Dakota, spawning a tornado in Nebraska and threatening dangerous thunderstorms from Oklahoma to Wisconsin.

A foot of snow had fallen by Friday morning in western South Dakota's Black Hills thanks to a storm slowly moving in from Colorado and Wyoming.

National Weather Service meteorologist John Chamberlain says the fall storm is one of the most intense to hit the area in a long time.

No travel is being advised along some western South Dakota roads, and some schools canceled classes. As much as 30 inches of snow could fall in the area.

Large hail and powerful winds were forecast to hit northwest Oklahoma later Friday, while storms were forecast from there into Wisconsin into Saturday.