Dense fog blankets the Valley

                  |   Watch Video Above for Extended Coverage   |

At least two schools cancelled class Monday morning in the south valley -- Tipton Elementary School District and Oak Valley Union Elementary.

There was a chain reaction accident at Manning and Lac Jac in Fresno County. Officers say a big rig driver lost control and jack knifed as he tried to stop at the intersection. The big rig hit a Dodge Ram and both cars went over the embankment. The driver of the Dodge pickup was taken to the hospital with major injuries.

Several other smaller collisions happened in the same area, involving as many as ten cars.

The low visibility also likely caused a three car accident in Fresno County on Jensen and Clovis. Officers say visibility was around 200-feet when a car ran a red light and crashed. One person is recovering from injuries at Community Regional Medical Center.

The thick fog is not just delaying drivers; air travelers in the valley are also dealing with delays. At least nine flights have been affected because of the low visibility at Fresno Yosemite International Airport.