CANADENSIS — For the past month, ambush suspect Eric Frein has capitalized on relatively mild temperatures, dense tree cover and his own survival skills to successfully elude a manhunt in the woods of Pennsylvania’s Pocono Mountains.

Now that it’s getting colder and the leaves are starting to fall, the advantage could soon shift to law enforcement, experts say. But the challenge remains no less daunting as police track an armed suspect — already accused of killing one officer and injuring another — in a wilderness that offers plenty of places to hide.

“I wish people could understand how hard it is to find people in the woods,” said Patrick Patten, who helped track Eric Rudolph, the 1996 Atlanta Olympics bomber who eluded authorities for years in the woods of western North Carolina. “It truly is a massive undertaking.”

The Sept. 12 ambush outside the Blooming Grove state police barracks killed Cpl. Bryon Dickson, seriously wounded Trooper Alex Douglass and touched off a manhunt whose scale is unrivaled in modern Pennsylvania history.

Each day teams looking for Frein creep through the woods around his parents’ home in Canadensis. Dogs sniff for explosives, weapons and ammunition — and any sign of the suspect. Troopers maintain a perimeter.

Residents have grown accustomed to the police presence. A woman fetching her mail seemed unfazed last week as more than a dozen camouflaged officers surrounded a vacant home across the street.

The massive manhunt has upset daily life in other ways, with schools closed and whole neighborhoods blocked off in the early days of the search, and retail businesses still foundering. An upcoming Halloween parade has been postponed and trick-or-treating this year is canceled.