SAN FRANCISCO (AP) – Fire crews from across the state are being deployed to Northern California where hot, windy conditions are renewing the threat of fire. The threat comes in the region where massive blazes have already destroyed hundreds of homes and killed 31 people this year. The National Weather Service issued a red-flag warning for extremely dangerous fire conditions from Wednesday through Friday morning. With bone-dry humidity and wind gusts possibly hitting 55 mph, Pacific Gas & Electric also may cut power Wednesday to as many as 54,000 customers in 24 counties. The shutoffs could last up to 48 hours.