SAN FRANCISCO (AP) — Crews have nearly doubled containment of a wildfire threatening thousands of homes in Northern California, as they brace for dry heat and erratic winds that could undo their progress. Fire spokesman Ryan Lubben says crews are focusing on expanding containment lines ahead of a red flag warning in the afternoon, when wind gusts of up to 35 mph are expected. On the heels of cooler, wetter conditions around the King Fire east of Sacramento that has burned 137 square miles and destroyed 10 homes, Tuesday is expected to bring winds up to 30 mph and low humidity that could bring a new surge. A red flag warning of very high fire danger has been issued Tuesday and Wednesday and could bring even greater gusts. About 2,700 people remain under evacuation orders, said state fire spokesman Daniel Berlant.