Heavy downpours to replace freezing fog An estimated 23 million people are predicted to hit the road next Saturday in the rush to get home before Christmas, according to a new study. Major jams are expected on Saturday 22 and more than half of people due to head out in their cars said they were concerned about weather and driving conditions, a survey by esure car insurance found. This morning In the Vale of York, visibility was less than 100m and conditions on the A1 and M1 were predicted to be difficult. However by Friday morning, the weather is likely to become milder and wetter, with the risk of heavy downpours in the south west. Temperatures could finally rise to as much as 11C in time for the weekend. Some places in the Midlands could see a jump of up to 8C between Friday and Saturday, forecasters said. Yesterday, Heathrow was forced to cancel around 60-70 flights on Wednesday while London City Airport also had to ground six planes as temperatures went down to -10C and freezing fog and ice caused havoc in large swathes of the country. There was congestion on a number of major road routes, while police were forced to close a three-mile stretch of the A24 southbound in the Horsham area of West Sussex after "treacherous" black ice caused 12 vehicles to skid and crash.