By Sam Elliott-Gibbs The Met Office has sounded an urgent weather alarm as Brits brace for a 283-mile blizzard before potential -10 temperatures. The alert has been issued as a plume of Arctic air will bring snow and spark sub-zero conditions in the coming days with the mercury projected to tumble. The forecast has prompted the UK Health Security Agency to announce an amber level cold-health warning and now the weather office has followed suit. A warning for snow and icy weather across parts of Scotland, north west England, parts of Wales and the Midlands has been issued. The alert comes into …