Fog warnings in Central Valley hoped will reduce accidents

Visibility along Highway 99 often drops to less than 100 feet, leading to dangerous conditions for drivers. If you've ever driven your big rig pulling a toad and run smack into a fog bank--and knowing you can't stop on a dime--it can be one of the most frightening experiences any RVer can experience. But the California Department of Transportation is hoping a new $12 million fog-warning system will help.

Sensors were placed along a 10.5-mile stretch from the Kings River to Manning Avenue in Fowler. The system is designed to give drivers about 30 seconds' warning before they drive into a fog bank. It was installed during the summer and first used in November.

The integrated systems involved include weather stations, electronic freeway message signs, microwave vehicle/motion detectors and visibility sensors. They will monitor weather patterns and traffic conditions, Caltrans officials said. The project is based on a smaller system in Stockton.

The stretch of highway in Fresno and Tulare counties was chosen because of the frequency of dense fog and reduced-visibility incidents in recent years. Crashes in the area have included an 18-car pileup in the fog that resulted in 10 injuries in 2008.