A fast-moving fire burning along Colorado 115 south of Colorado Springs blew the containment line Thursday, spreading farther east onto Fort Carson and scorching nearly 700 acres, officials said.

The blaze, known as the 24 fire, was fully uncontained as of late Thursday afternoon, officials said, despite having been 50% contained earlier in the day. Smoke will remain visible along the highway as crews try to corral the flames.

The National Interagency Fire Center (NIFC) estimated the fire perimeter had grown to 670 acres. Fort Carson officials earlier in the day reported the 24 fire size at 80 acres.

Highway 115 was closed Thursday evening between County Road F45 (3 miles north of the Penrose area) and Barrett Road (10 miles south of the Rock Creek Park area) from mile marker 21 to mile marker 28, according to the Colorado Department of Transportation.

The wildfire was one of three burning across southern Colorado this week amid dry, dangerous fire weather conditions that were expected to increase in the coming weeks. According to the Rocky Mountain Area Coordination Center, all three wildfires were caused by humans.

Fort Carson officials said the plan moving into the Thursday night was to place control lines on the southwest side of the fire to keep it on the east side of Colorado 115.

“In the morning (Friday) aircraft operations will resume,” the officials said in an email update.

In an update Thursday afternoon, a Fort Carson spokesperson said a separate, 1,600-acre wildfire burning within the Army base’s training area was 100% contained.

Full containment means fire lines holding the perimeter of the fire are secure, preventing the fire’s spread.

Buttermilk fire in Custer County largely contained

In Custer County, a wildfire that prompted evacuations near Westcliffe on Wednesday was 75% contained Thursday. The Custer County Sheriff’s Office said Pines Ranch and Spread Eagle neighborhoods were reopened to residents at noon Thursday, but urged them to stay in the “ready” stage for evacuation.

Fifteen homes remained under mandatory evacuation. Deputies were assisting the residents in gathering supplies and removing pets whenever it was safe to do so.

Dubbed by officials as the Buttermilk fire, the Custer County fire began burning on Wednesday and has scorched an estimated 80 acres, according to the most recent update from the county. No injuries have been reported, and zero structures have been lost.

The office initially reported the wildfire was 80% contained, but later said that estimate was “incorrect.”

According to the latest update, the fire started after an aspen tree fell onto a power line, which has an automatic setting to try to reconnect the power. For the duration of the fire season, the automatic reconnect feature will be disabled, the Custer County Sheriff’s Office said.

“This potentially would lead to more outages due to false alerts. Anytime a failure is detected, they will have a manual crew physically check the lines before re-energizing,” county officials said in the latest update.

Mykel Kroll with the Fremont County Office of Emergency Management said it’s critical that people start paying attention to fire weather safety.

“We’ve had a very dry winter. Getting people prepared is going to be huge this season. People need to be signed up for alerts,” Kroll said.

In El Paso County, Fort Carson officials have not shared more details on how the two fires were sparked, but they said the fire along Colorado 115 started off post before spreading onto the military base.

Kroll estimated that it will take at least a few days for the fire along the busy highway to be fully contained. It could be even longer, Kroll said, due to the rough, mountainous terrain fire crews are navigating and changing weather conditions.

“At this time, the winds are very, very well in our favor and pushing the fire back towards the east, away from Highway 115,” Kroll said late Thursday morning — before it jumped containment lines.

Record-breaking heat in the forecast

The National Weather Service in Pueblo said record warmth will continue through Saturday for southern Colorado. High winds over the weekend will bring increased fire danger for much of the region.

Thursday’s high temperature for Colorado Springs was 81 degrees, tying the city’s all-time high temperature in March, according to KOAA meteorologist Casey Dorn.

Daily elevated fire weather conditions were expected across the higher terrain Friday and would likely spread east into the plains Saturday due to gusty winds and “very low” humidity values, according to the National Weather Service.

Friday’s expected high temperature in Colorado Springs is 83 and Saturday the forecast calls for 89, with sunny skies both days. Temperatures are nearly 30 degrees above the average this time of year.

Meteorologists from the U.S. Climate Prediction Center are predicting that the temperature and precipitation outlook this spring “leans” to above-normal temperatures and below-normal precipitation.

The Gazette’s Mary Shinn, Alexander Edwards and Tony Raap contributed to this report.