Snow and ice will hit Stroud tonight and on Sunday, according to the Met Office.
They have warned road users of travel delays and rail cancellations, and residents of cuts to power and mobile phone coverage.
People should expect some icy patches on some untreated roads, pavements and cycle paths - so be weary of slips and falls.
Further rain is expected to spread from the southwest through the day, heavy at times, according to the Met Office.
The south coast and Dartmoor can expect the heaviest downpours.
This evening, rain will clear across the region, leaving a dry but largely cloudy night.