By Kieren Williams UK weather maps have plunged dark purple with heavy snow set to hit after a Met Office warning. With temperatures set to plunge as low as -9C, snow and ice have swept across huge parts of the UK in recent days. Even in parts of southern England snow has been falling, including in the capital, but the country is far from out of the woods. Weather maps from WXCharts show that even in coming days and weeks, heavy snowfall could still return to the UK. For January 17, parts of the southwest of England, East Anglia, Midlands, parts of Wales and across the Irish Sea could all see …