MADISON, Wis. (AP) – A ferocious winter storm has left thousands of Wisconsin residents without power and caused at least two major rollover crashes in Dane County.  State emergency officials say the storm has cut power to about 2,300 Madison Gas & Electric customers in the Madison area; nearly 1,900 Alliant Energy customers through south-central and southwestern Wisconsin; about 450 We Energies customers in the Oshkosh area; and nearly 3,000 Wisconsin Public Service Corporation customers in the Manitowoc and Two Rivers areas.  State officials say all the utilities are working to restore power.  Wisconsin State Patrol officials report a semi-trailer jackknifed on Interstate 39/90 near Stoughton. Another semi-trailer rolled over on I-90 near DeForest and Waunakee. The State Patrol says both accidents caused back-ups but have been cleared.