RENO, Nev. (AP) — More than 1,300 firefighters worked to reinforce lines and aerial crews stepped up attacks ahead of gusty winds at two big Nevada wildfires on Monday, including one threatening to force evacuations at a tribal community northeast of Reno.

The National Weather Service issued a red-flag warning through Tuesday evening across nearly all of northern Nevada where the fire threat has been elevated because of a combination of winds expected to gust to 35 mph (56 kph), low humidity and temperatures from the mid-90s to near 100.

"A red flag warning means that critical fire weather conditions are either occurring now, or will shortly," the weather service said Monday afternoon.

The U.S. Bureau of Land Management issued an evacuation advisory for the town of Sutcliffe on the edge of Pyramid Lake after flames burned Sunday night within a mile of the tribal community 35 miles (56 kilometers) northeast of Reno.

The BLM said tribal police will go door-to-door to notify residents in the event a mandatory evacuation is ordered. An evacuation center was being prepared at the school gym in Nixon southeast of the lake.

"The fire conditions may change without warning," the agency warned Monday. "The situation is dynamic."

The Pyramid Highway (State Route 445) was closed in both directions north of its intersection with State Route 446 south of Sutcliffe.

Nearly 900 firefighters were assigned to that Long Valley fire, which has burned an estimated 130 square miles (337 sq. kilometers) since it broke out July 11 in Doyle, California, near the Nevada line. It was estimated Monday to be 35 percent contained.

"Firefighters are holding, strengthening and constructing direct and indirect lines," the agency said.

In north-central Nevada, more than 500 firefighters continued to battle a complex of four fires that have consumed 182 square miles (471 sq. kilometers) of mostly grasses and brush north of Winnemucca and Battle Mountain.

No evacuations were ordered, but the mining town of Midas was on standby and the Pershing County sheriff was recommending voluntary evacuations in remote areas north of Interstate 80. The fire is not expected to be fully contained for another week.

In addition to high winds and rugged terrain, firefighters have been hampered by unusually hot weather and unusually high brush growth spurred by a very wet winter.

The temperatures in Reno surpassed 90 degrees for the 32st consecutive day on Monday. That stretch is now three shy of the record 35 days set in 2005 and tied in 2008 and 2010. On Sunday, Tonopah tied its record high of 100 degrees set in 2006.

The red flag warning stretches from wast of the California-Nevada line to south of Hawthorne, north to the Idaho border and as far east as Wells about 60 miles west of the Utah line. It was scheduled to expire temporarily at 8 p.m. Monday and resume at 2 p.m. Tuesday.