The Missouri State Highway Patrol says 50-year-old Robin Thomas died when she lost control of her car north of St. Joseph.
The accident happened on the southbound US 71 exit ramp onto I-29 around 6:20 a.m.
Troopers say Thomas lost control of her car on the wet highway and spun off the road.
The drivers side of her vehicle hit the guard rail.
Thomas was pronounced dead at Heartland Hospital.
Troopers say Thomas was not wearing a seat belt.