The Mullen Fire in Medicine Bow National Forest doubled in size Saturday, reaching nearly 70,000 acres.
Communities near the Colorado border in Albany County have been evacuated as the more than 400 firefighters on-site prioritize protecting homes and structures.
"We're in total defensive mode," said Fire Information Officer John Peterson. "We're not doing anything proactive or trying to contain this thing. We're just trying to protect homes, infrastructure and property in these communities."
The fire crews were expecting conditions to worsen heading into the weekend, but 50 mile-per-hour winds quickly became 70 mile-per-hour winds, helping to double the fire's acreage Saturday morning.
Weather conditions are not the only problem worsening the blaze, however.
"We can't get the resources we need," Peterson said. "We have over 400 firefighters on this fire but it's a huge fire and it's moving hard. It's just hard to get resources because there's so many fires in the country going right now."
Peterson said the crews are hoping for better weather conditions and more favorable terrain. The wind is expected to let up slightly, and there's even a chance of a little precipitation in the forest Sunday.
"My understanding is that as this fire moves east, it's going to move into a different vegetation type - it's going to move into sagebrush-grass," Peterson said. "And in sagebrush-grass, particularly if there are moderate winds, we can fight it fairly effectively. If our aircraft can fly, aircraft can very quickly suppress fire that's blowing through sagebrush and grass, if the wind isn't 70 miles-per-hour."
There are more than a dozen aircraft currently helping firefighters in Medicine Bow, including both planes and helicopters.
But Peterson said it's going to be a long duration fire, and the crews won't be able to start containing it until the weather and location improve, or until more firefighters arrive to aid the cause.
"This fire's going to go and go and go," Peterson said. "And we're going to keep corralling it, trying to keep it up in the forest and out of people's backyards."
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