By Lois_AveryWednesday, January 06, 2010, 15:43Police have issued a SEVERE weather warning across Wiltshire as the Big Freeze takes hold of the county today. The extreme weather warning for Wiltshire, which was issued yesterday, has now been re-assessed as a severe weather warning. The update followed a meeting held at today by Wiltshire police and, the County Council and other agencies. Snowfalls are expected to continue in parts of Wiltshire for the remainder of the afternoon, and temperatures could easily drop to -10 degrees overnight. The Met Office has said that no significant thaw is expected for a number of days.