Drivers have faced testing conditions in Cornwall with sub-zero temperatures leading to icy roads.
Temperatures dropped to -6C in parts of the county overnight and the Met Office warned of widespread ice.
Firefighters rescued an ambulance which got into trouble near Launceston. Two crews used ropes to pull it free after it got stuck on a steep hill.
Salting is continuing, but highways bosses said they needed to conserve supplies until they had new deliveries.
Peter Tatlow, from Cornwall Council's highways department, said: "With every day that goes by and no delivery, obviously the stocks are going down.
"We're doing our best to eke it out until the next supply comes through."
Highway bosses said abandoned vehicles littering minor roads have added to motorists' problems.
First Buses said all services were operating but could be disrupted by icy roads.
Newquay Airport said its flights were running but delays were possible.
A few wintry showers were due to spread to west Cornwall later, the Met Office said.
There could be some snow flurries or wintry showers tonight, with temperatures again falling to -3C, it added.