A major weather pattern change has arrived on the West Coast, bringing relief for California’s wildfires and choking smoke, but it may also unleash enough rain to trigger dangerous debris flows in recently burned areas of the state. Northern California’s Camp Fire, the deadliest and most destructive wildfire on record in state history, is still not fully contained. Smoke from the fires has hung over millions, fouling air quality since last week in the Central Valley and Bay Area. Air quality has begun to improve but remains unhealthy for sensitive groups on Wednesday in the Central Valley of California.