(CBS4) — The East Troublesome Fire grew almost another 50,000 acres on Thursday, after growing about 100,000 acres Wednesday night. As of Thursday evening, the fire was estimated at 170,000 acres — making it the second largest fire in Colorado history.

East Troublesome Fire (credit: John Erwin)

“We prepare for the worst. This is the worst of the worst of the worst,” Grand County Sheriff Brett Schroetlin said.

There are concerns the fire could merge with the Cameron Peak Fire, which has burned over 200,000 acres.

“It is a potential, and certainly this year has been one of those years where those low potential events seem to be happening with high frequency,” Noel Livingston, incident commander, said Thursday night. “And, you know, a fire of this size, moving this far in October is a very low potential event in terms of what we would expect, and it’s occurred.”

“I don’t want to say you can’t happen right now. It doesn’t appear that it’s going to,” Livington said.

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Livingston called it “an amazing amount of fire spread” in a Thursday morning briefing.

“Obviously yesterday was a significant fire day,” said the fire manager. “We saw about 20 miles of fire growth through the afternoon and into the night, which equates to about 100,000 acres of additional fire activity.”

“That’s really unheard of for a fire in this part of the world, in timber,” Livingston said Thursday evening.

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Livingston said the East Troublesome Fire’s growth on Wednesday can be explained by several factors: strong winds, excessively dry conditions, low relatively humidity and beetle-kill trees among the fuels in the high elevations the wildfire spread through.

Colorado’s largest wildfires:

  1. Cameron Peak – 2020 – 206,667 acres
  2. East Troublesome Fire – 2020 – 170,000 acres
  3. Pine Gulch – 2020 – 139,007
  4. Hayman – 2002 – 137,760
  5. Spring Creek – 2018 – 108,045
  6. High Park – 2012 – 87,284

Anica Padilla