Here in North Northumberland the car thermometer increased from -4 to -1 in the space of 2 miles, no change in altitude, totally clear skies, light snow cover, reason - it's a west wind, sheltered places are soooo much colder, hoping for a nice southerly later in the night. If I'd driven another 5 miles SE I'd have hit 10cm of snow rather than our 1cm, again same altitude but nearer the coast and the other side of a hill!