Fog in the forecast
It's up there with the worst driving conditions when it's bad for sure. I remember back in the Land Rover days having to avoid an accident and resulting traffic on the A38 by heading for the dark lanes near Breadsall. The fog was so bad (even with fog lights) that I had to lean out of the window to see where the white line was!
Is the transition from cold to mild responsible for the forecasted fog?