A dangerous cold weather spell that could result in "higher mortality rates" among the vulnerable has been extended by another week. 

The alert was initially issued from Sunday until this Friday but it has now been pushed until next Thursday, bringing with it a "brisk" easterly wind and frosts. 

Freezing temperatures and reports of black ice on roads across the county have prompted Norfolk Fire and Rescue Service to caution wary drivers, saying even the most careful can be caught out. 

The UK Health Security Agency said: "Significant impacts are probable across the health sector including an increase in mortality in the 65-plus age group but impacts may also be seen in younger age groups.

"Maintaining indoor temperatures at 18C may become challenging for some, leading to an increased risk for vulnerable people.

READ MORE: Snow and 'disruptive' weather could hit Norfolk next week

"Staffing issues may occur which could impact transport and energy sectors."

The Met Office has said there is an "increasing chance" of snow next week as temperatures look set to plummet to -3C.

Metdesk predictions show Norfolk could be severely hit by heavy snow and rain as soon as next Wednesday as low-pressure moves in from the Atlantic.