Dozens of gritters are and about on Hertfordshire's roads with the county set to see one of its coldest nights in years.

The Met Office is predicting freezing temperatures overnight which could drop as low as -5 degrees celcius in rural areas by dawn (January 6).

St Albans and Harpenden look set to see temperatures hover around -2 and -3 before it gradually warms up after Thursday's rush hour.

It will be the coldest night seen so far this winter and Hertfordshire County Council says temperatures of around -5 will be the lowest for "several years".

In response to the cold blast, the council says its fleet of gritters will be out on two runs tonight to salt roads across the county with road temperatures expected to drop to -5.

More than 1,500 miles is set to be covered - nearly half of Hertfordshire's entire road network - including A and B roads, bus routes, at least one route into every village, and roads with a 10 per gradient or steeper.

The council, which also sent gritters out this afternoon, says it will aim to grit roads leading to schools, surgeries, care homes, key pharmacies, and libraries.

Drivers are being urged to drive cautiously as the cold weather sets in.

Phil Bibby, executive member for highways and transport at Hertfordshire County Council, said: "Please remember to always drive to the conditions, especially at this time of year. Just because it doesn’t look like there is ice doesn’t mean the roads are not slippery.

"If temperatures drop below zero and there is any moisture in the air, they can still be slippery."

There are no freezing temperatures forecast for the following days although it will feel very cold particularly during nights.