‘A nuclear winter’ over San Francisco bay area, as wildfires blot out the sun

Across Northern California, giant plumes of smoke from a fire that blasted through the foothills of the Sierra Nevada billowed and spread high in the atmosphere, blotting out the sun.Across Northern California, giant plumes of smoke from a fire that blasted through the foothills of the Sierra Nevada billowed and spread high in the atmosphere, blotting out the sun.