ESTES PARK, Colo — The winter winds roar off the Continental Divide in Rocky Mountain National Park relent lessly, blasting our little town with such ferocity that sometimes I fear we might blow away. It’s as if the mountains are finally exhaling now that the peak of the tourist season has passed. For most of its history, Estes Park, the gateway to Rocky Mountain National Park, has been a ghost town in winter. Over the last several years, however, with the population boom along the Front Range of the Rockies and the growing popularity of our national parks, Estes has nudged itself toward a sustainable year-round economy. Barely. Precariously.

But now, with so many locals having banked on a small but steady stream of income tied in various ways to the park — the fourth most visited national park in 2017, with 4.4 million visitors — the government shutdown has upended the economy of this town and created apprehension and uncertainty.

“It’s crazy that one guy gets to do this to us all,” said Dustin Dyer, director and co-owner of Kent Mountain Adventure Center, a guide service that’s been here for decades, referring to President Trump.

Although Rocky Mountain National Park officially remains open, its main roads had been closed until this week, because there wasn’t enough money to run the snowplows. Well over half of Mr. Dyer’s trips (he offers snowshoeing, backcountry ski touring, ice climbing and avalanche courses) had to be canceled, but he’s trying to be optimistic. “We will survive, but it is crazy to be hit by the noise on the TV,” he told me. “It is usually just noise.”