Had* to visit Kettering after work last night, the sky's went a horrible dark grey and lightening started, it was about 18:30.
Within 10 minutes the temp dropped from 7 to 2 deg's and there was a huge snow/hail storm with at least 2 to 3" of what can only be described as miniature snow balls on the ground; these quickly compacted down and turned to smooth ice

going down hill at 40mph I merely 'covered' the brake and the ABS kicked in

we were fine but we saw 4 accidents within half a mile it was like something out of a film, weird.
I've never driven where the conditions changed so quickly.