Motorists have been warned to take care (Photo: Jonny Wardle)
Grit supplies could run out in Worcestershire over the next few days, council leaders have warned.
Worcestershire County Council said the remaining salt was being rationed in order to try to cope with the continuing cold weather.
Forecasters have warned parts of the West Midlands could have 8in (20cm) of snow overnight and on Thursday.
The council said priority grit stock was going to the Highways Agency to clear motorways and other main roads.
A spokesperson added grit bins would not be refilled until extra stocks were found.
They said the council had ordered "enough" rock salt before Christmas and again in January but the recent demands had meant their suppliers were now running low.
The spokesperson said that put Worcestershire "in a very difficult position", but the situation would be monitored on an hourly basis.
Warwickshire County Council and Birmingham City Council have already said they would be rationing their gritting stocks.
Three schools have remained closed in Herefordshire and Worcestershire.
The Coppice Primary School and Woodrush Community High School, both in Hollywood, Wythall, Worcestershire, were closed.
Meadow Green Primary School, in Wythall, was also closed as snow continued to fall, mainly in high areas.
Police have urged drivers to take extra care on the roads.
Herefordshire council's gritting service said it had been one of its busiest winters so far.
It had been "working round-the-clock" with its contractors Amey to ensure the county's roads were safe during the heavy snowfalls, a spokesperson said.
Some 1,700 tonnes of salt was spread on the county's roads over three days.