FORT COLLINS, Colo. (AP) — One of two Rocky Mountain wildfires that have been pushed by strong winds has become the largest in Colorado’s history. The Cameron Peak Fire has burned 256 square miles in northern Colorado as of Thursday. That’s about 40 square miles bigger than one in western Colorado that held the previous record and was fully contained Sept. 15. Meanwhile, the Mullen Fire in southeastern Wyoming and northern Colorado has burned 276 square miles. Forecasters expect dry air and strong wind to pose a challenge for firefighters into the weekend. The burning is occurring much later in the year than usual.