P_Wei/Getty Imagesweather event, low-elevation snow is expected across California as a storm system ushers in exceptionally cold air into the state Tuesday through Saturday. Travel impacts are expected in the Central Valley, especially on the western side, and in the foothills, with light snow possible Wednesday and the heaviest snow expected on Thursday and Friday, the weather service's Sacramento office said. The I-5 Grapevine is likely to see impacts; it's not unusual for the mountain pass to temporarily close in snow events