A yellow warning for ice and snow is in place across Devon and Cornwall, and is scheduled to last until Tuesday.
The Met Office has warned of scattered sleet and snow showers, external, and icy patches which may cause some travel disruption on Sunday, Monday and into Tuesday morning.
The ice, sleet and snow warnings start at 12:00 GMT on Sunday and run continuously until 11:00 on Tuesday.
Some roads and rail journeys are likely to be affected and there is an increased risk of injuries from slips and falls on icy surfaces.