CHEYENNE, Wyo. \u2014 As the Mullen Fire swelled to nearly 20,000 acres yesterday, the team fighting the blaze more than tripled in size to 367 personnel as firefighters battle ripe fuels and red flag warning conditions. With wind gusts today expected to top 40 mph, firefighters are poised for another big run today as the fire finds plenty of available fuels in tinder-dry beetle-killed lodgepole pine with heavy dead and downed fuels. The fire is at an estimated 19,526 acres at 2% containment. The fire spread to the northeast yesterday prompted the cutoff of electricity by Carbon Power and Light to the evacuated areas west of Albany, including the communities of Keystone, Lake Creek, and the Rob Roy Reservoir area. Both ground and aerial firefighters are working furiously to protect property in the challenging conditions today. But if weather and fire conditions become unsafe, Incident Commander Jared Hohn will not hesitate to pull his firefighters out of danger. Fingers of fire have crossed the 500 Road to the northeast. Fire is entering the Keystone Fire burn scar, and impacting the 512 Road. The southeast part of the fire is also moving to the northeast. Thursday recap Yesterday was hellish. Significant activity was recorded all around the fire, pushed by strong southwest winds with gusts to 30 mph that continued well into the night. Winds were extremely adverse on the fire\u2019s north, southeast, and east flanks, and firefighters were unable to slow the fire\u2019s advance. On the east, the fire ran to the southern edge of Rob Roy Reservoir, one of the City of Cheyenne\u2019s sources of drinking water. The southern tip of the fire moved to the east, crossing the 512 Road and approaching the Keystone communities. As fire activity intensified, many firefighters moved to successfully defend structures in the Rambler community and the Keystone area. Today\u2019s plans A very active day is expected Friday with weather conditions similar to yesterday. Firefighters expect to see significant growth to the east and northeast of the fire, and winds may affect air operations. Structure protection crews will work to defend homes and structures in the evacuated areas. Fire and county officials are coordinating efforts to ensure the public is aware of rapidly changing conditions. Forest area closures are expected to be expanded today as well. Mandatory evacuations \tLake Creek community \tRambler community \tRob Roy community \tKeystone communities: Keystone proper, lower Keystone, Langford\/Ricker, Moore's Gulch, and 507C cabin grouping Pre-evacuation notice \tPrivate land along Fox Creek Road \tThe communities of Albany and Centennial, extending northwest along Highway 130 \tAll areas west of Highway 11 in the valley. Temporary Flight Restriction\u00a0 A Temporary Flight Restriction is in effect for the fire area.\u00a0For the safety of all firefighters, all private aircraft, including drones, must avoid this area. If you fly, firefighters can\u2019t. A community information meeting on the Mullen Fire will be live-streamed today at 3 p.m. The cause of the Mullen Fire is still under investigation.