Devon County Council is preparing to salt the entire network for the first time this winter.
Temperatures are forecast to drop as low as -3C on Dartmoor and the rest of Devon will plummet below freezing.
The concern is that following heavy rain over the weekend there may still be some surface water on the roads.
If that becomes icy then driving conditions could become treacherous, especially on untreated routes.
Devon County Council's gritters will be out across the county from 6pm this evening, treating around 1,650 miles on all of the county's 48 salting routes.
Further inspections will be carried out early tomorrow morning.
Councillor Stuart Hughes, Devon County Council Cabinet Member for Highways and Transportation, said: "After the torrential rain we've just had, ice could become a problem in some areas. This is the first real cold snap we've had this winter so it's worth remembering that even on roads that have been salted, ice can still form. I would urge motorists driving overnight and tomorrow morning to take care."