A wildfire that broke out Monday west of Silverton in the San Juan Mountains, trapping about 20 hikers near the popular Ice Lakes trailhead, quickly grew to an estimated 320 acres by the end of the day.

On Monday afternoon, reports started coming in about a fire a quarter-mile up the Ice Lakes trail in a heavily wooded area. An initial assessment had the fire at about 20 acres as of 2:30 p.m.

The official name of the fire is the Ice Fire.

Because of the difficult and steep terrain, an aggressive aerial attack was called for, said U.S. Forest Service spokeswoman Esther Godson.

Godson said an air-attack fixed-wing aircraft and a Type 2 helicopter with a helitack crew were on-scene as of 3:10 p.m.

As of Monday night, one air-attack fixed-wing aircraft, five helicopters, six single-engine air tankers, four fire engines, one fire suppression module and a helitack crew were assigned to the fire. Additional resources, including three hand crews and one water tender, have been ordered.

The number of ground crew members available was not immediately clear Monday, Godson said. But ground crews that are on scene have been working to protect South Mineral Campground and hold fire from spreading south of South Mineral Road. The fire was burning only on the north side of the South Mineral Road.

Also as of Monday night, the San Juan National Forest Type 3 Incident Management Team assumed control of the Ice Fire. Godson said the team is expected to provide a better idea of the fire’s potential growth, as well as a firefighting strategy, on Tuesday.

One major challenge, Godson said, is that firefighting resources are extremely limited as wildfires actively burn throughout the West, especially in Colorado and California.

The Cameron Peak Fire burning near Rocky Mountain National Park, for example, is Colorado’s largest wildfire in recorded history, growing to more than 200,000 acres this past weekend.

“Resources are extremely tight,” she said.

Immediately after the Ice Fire broke out, South Mineral Road (Forest Service Road 585), a popular area for camping, which leads to the Ice Lakes trailhead, was closed and evacuated.

About 20 hikers were trapped above the fire and required rescue by helicopter, said San Juan County spokeswoman DeAnne Gallegos.

Greg Anson of Carbondale was on a day hike to Ice Lake when he noticed a “massive” plume of smoke around 1 p.m.

Anson and about 20 other hikers visiting Ice Lake grouped together to decide what to do, debating whether to try to find a way to hike out of the area or wait for help.

“There was a little tension whether to wait or hike,” he said. “Some people didn’t think they could make it.”

The first helicopter landed to rescue the hikers about 30 minutes after the smoke was noticed. It took four flights to extricate the hikers. Anson said he was ferried to safety and landed about 3:15 p.m.

“It was crazy,” he said. “I’ve never been through anything like that.”

No evacuation orders had been issued as of Monday night for the town of Silverton.

Still, some residents were preparing for the worst. Bryon Powell, a Silverton resident and professional runner, said he had prepared Monday in case evacuations are issued.

“It’s grown incredibly over the last hour,” he said at 2:45 p.m. Monday.

Fire danger has remained high in Southwest Colorado during the past few weeks, with Stage 1 fire restrictions in place in the San Juan National Forest.

The Ice Lakes trail is one of the most popular and heavily used in Southwest Colorado.

About 7 miles west of Silverton, the trail, which starts at an elevation of 9,840 feet, climbs a couple thousand feet to two stunning, turquoise alpine lakes: Ice Lake and Island Lake.

The alpine lakes are commonly featured on best hike lists in Colorado and shared on social media. On any given day in the summer, hundreds of people make the trek to the lakes, leading to significant resource damage in recent years.

Godson said it remains unclear what started the fire.

Southwest Colorado has experienced no lightning storms in weeks, said Erin Walter, meteorologist with the National Weather Service in Grand Junction.

This week’s weather forecast is not encouraging news for slowing down the fire’s spread, Walter said. Wind gusts were expected to reach up to 30 mph Monday in certain areas, and a weather system moving into the region over the next couple of days is expected to increase wind speeds even more.

“Dry and gusty winds are not helpful for any fire growth,” Walter said.

No precipitation is in the forecast this week, save for a slight chance of rain Friday night and Sunday, according to the National Weather Service.

Godson said fires typically die down overnight as humidity settles over the region, but because it’s been so dry lately, that may not be the case with the Ice Fire on Monday night into Tuesday morning.

She also cautioned that smoke will affect travel on U.S. Highway 550, and drivers should not stop to take photos of the fire.

“(Highway 550) is going to be impacted by smoke for the duration of this incident,” she said.

An air quality health advisory for wildfire smoke was issued for San Juan County, including Silverton, until 9 a.m. Tuesday, according to the Colorado Department of Public Health and Environment.

Godson said it is likely surrounding communities will be affected as smoke disperses and settles Monday night.

jromeo@durangoherald.com