* WHAT...Northwest winds 25 to 35 mph with gusts up to 60 mph.
* WHERE...Portions of northwestern and southwestern South Dakota.
* WHEN...Until 6 AM MST Tuesday.
* IMPACTS...The high winds may damage roofs, small outbuildings, and signs. Power outages are possible. Travel could be difficult, especially for high profile vehicles. Strong winds can cause blowing dust, reduced visibility, and flying debris.