The Mullen Fire in Medicine Bow National Forest doubled in size Saturday, reaching nearly 70,000 acres - and has since surpassed 80,000 acres.
Communities near the Colorado border in Albany County have been evacuated as the more than 500 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.
More moderate weather Sunday and Monday - including 5/100ths of an inch of precipitation Sunday - is giving fire crews hope heading into another week.
The change in weather is also giving crews the chance to prepare and defend evacuated communities within the forest.
Peterson said that's happening now.
"Some communities have fire in them right now," he said. "Some are waiting for the fire. It will be there, we anticipate, in a day or two."
The fight is far from over, however.
"As the week goes on, it's going to dry out," Peterson said. "It's going to get warmer and we're going to have persistent wind. I won't say the winds are going to dramatically pick up, but they're going to be present every day."
Weather conditions are not the only problem worsening the blaze, however. The firefighting effort is also hampered by a shortage of firefighters, due to other fires throughout the West Coast and Mountain West.
"We can't get the resources we need," Peterson said. "It's just hard to get resources because there's so many fires in the country going right now."
There are, however, 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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