The icy roads led to a fatal crash west of Big Timber Wednesday morning.
It happened on eastbound interstate 90 at mile marker 364 around 9 a.m.
The driver of a Ford Explorer lost control, according to Montana Highway Patrol Trooper Erick Fetterhoff.
The vehicle went into the median and rolled four times.
The man from Georgia was not wearing a seat belt and was thrown from the vehicle.