RUMFORD — Despite Tuesday’s inch or so of rain, conditions across western and central Maine are ripe for stubborn forest fires of 10 to 100 acres or more, Maine Forest Service officials say.

That’s why the state fire danger suddenly jumped Monday from moderate to high from Gilead to Greenville and from Fryeburg and Lewiston-Auburn to Bangor.

“The thing that’s probably confusing people right now is that we’ve enjoyed a summer of Class 2 days, which means a moderate fire danger,” Ranger Jay Bernard said Tuesday.

“And we’ve gone to a Class 3 day on the eve of rain, so everybody’s been going, ‘Well, what the heck? It’s raining, and it’s a Class 3 day?'” Bernard said. “It could rain like it did last night, and then turn around and be sunny and windy, dry that fine-fuel out, and then we’ve got high fire danger and a recipe for a forest fire.”

Fine-fuel is anything that will carry fire, such as tree needles, leaves and small twigs.

“The rain takes care of the fine-fuel moisture for about 24 hours or even less, sometimes within 12 hours,” Bernard said. “If we’ve got sun and wind, it can turn that fine-fuel into a dry, fire-carrying fuel. So that’s why it’s just as volatile right now as we’ve had in periods this spring.”

It’s also why the forest service issued a bulletin Monday urging campers and those working in the woods with machinery to use extreme caution.

The Danforth fire, which was found Monday afternoon near the New Brunswick border, jumped from 5 acres to 10 acres in less than 24 hours, said Kent Nelson, a Maine Forest Service fire prevention specialist.

A mechanical timber harvesting operation in the area may have caused it. Elsewhere, smaller forest fires are whooshing up after escaping from campfire rings.

Campers should thoroughly extinguish fires and check several times before leaving the area, Nelson said. “Those wishing to burn brush piles are asked to wait until we get a significant rainfall.”

Despite Tuesday’s rain and last month’s deluge that flooded Lewiston-Auburn downtowns, the ground is “very dry,” Bernard said.

In the past several days, rangers have seen “a significant drying trend” in the forest floor, Nelson said.

“We are looking at significant buildup indexes,” Bernard said. “We’ve compared (the buildup index) to serious fire seasons we’ve had in the past, and while all the ingredients of a forest fire recipe aren’t there yet, the buildup is looking very ominous.”

On Monday in Woodstock, a man using a cutting torch on a camp trailer inadvertently caused a woods fire that threatened two structures when the camp trailer ignited and burned, Bernard said.

He credited a quick knockdown from Woodstock firefighters with containing the woods fire and keeping it small, while also extinguishing the initial structure fire.

“We’ve had a good local response and they need to stay on top of it or we’re going to be looking at some big fires, over 10 acres or over 100 acres, even,” Bernard said. “We can go from low fire danger to extremely high fire danger in the course of a day, so be vigilant.”

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