Amid a run of dry weather, the fire danger has grown across much of Maine as crews battle several wildfires, including a 30-acre blaze near the Canadian border and a stubborn underground fire in a wooded area of Biddeford.

Fire officials are warning people to be extra careful because the dangerous conditions are unlikely to improve in the short term. There is no significant rainfall expected in the next week, and more than 35% of the state is considered to be abnormally dry.

There have been 508 wildfires in Maine this year as of Wednesday, burning about 393 acres, said Terri Teller, a forest fire prevention specialist with the Maine Forest Service. More than 100 of those have occurred in August.

Maine Forest Service rangers have responded to dozens of wildfires this week and on Wednesday issued a warning on social media about the very high fire danger. Local fire wardens have stopped issuing burn permits, a move that the forest service supports. The state’s online permit system is shut down, and the forest service is not issuing any open burning permits.

“In many parts of the state local authorities have implemented restrictions to open burning based on fire danger and their ability to respond to wildfires,” the forest service wrote in a Facebook post.

The forest service said Wednesday that all of southern, central and western Maine, plus some areas north and east of Millinocket, are now considered to be in very high fire danger, which is the second-highest level. The rest of the state is classified as high fire danger.

Teller said Maine tends to reach the very high level a few times each year — especially during April and May, which is peak season for brush fires — but it’s unusual for the risk to be so high in August.

When the fire danger is considered very high, fires can start easily from all causes, spread rapidly and intensify quickly. Spot fires are a constant danger, the forest service said. In areas with high fire dangers, unattended brush and campfires are likely to escape and spread quickly.

The forest service assigns daily fire danger ratings based on temperature, humidity, wind speed, recent precipitation and fuel moisture content.

Sarah Jamison, a meteorologist with the National Weather Service office in Gray, said the fire danger is a growing concern. Conditions across Maine started to get a little dry earlier this summer but rapidly declined coming into August because there has been little or no rainfall for much of the state, she said.

Most of Maine is now 3 to 5 inches of rainfall below normal, Jamison said, and lake and stream levels are dropping, exacerbated by recent stretches of hot weather.

In the next week, some scattered showers may develop in parts of the state, but not the wetting rainfall — more than a quarter inch of widespread rain — that is needed to make a difference for fire conditions, she said.

“Unfortunately, the prognosis is not a very bright one,” Jamison said.

CREWS BATTLE BLAZES

On Monday evening, the Biddeford Fire Department began receiving 911 calls reporting heavy smoke coming from the woods behind the Home Depot and Cumberland Farms on Alfred Street.

Firefighters found the fire nearly 3,000 feet into the woods behind the Home Depot and called in backup from the forest service and seven surrounding communities. They have stretched thousands of feet of hoses into the woods to get water onto the area, said Biddeford fire Chief Larry Best.

The next day, 17 firefighters from Biddeford, Saco, Kennebunk and the forest service continued their attack on the fire, which Best said likely started from a campfire. Crews have been using axes and other hand tools to get at underground spots where fire keeps popping up, he said.

“It’s so dry out there, and the fires are burning deep into the ground, which is a real challenge for us,” Best said Wednesday. “We get it out, and then we have to go back to continue digging it up and wetting it down.”

By Wednesday, crews were using a forest service truck to dump 300 gallons of water at a time on the fire. Best said crews have been able to contain the fire to an area that’s a little under 2 acres.

Meanwhile, in Acton, fire crews have spent two days fighting a brush fire on Sanborn Road. On Wednesday afternoon, fire crews there struck a fourth alarm to call in more assistance.

In Down East Maine, at least three wildfires have been reported in the past week, most notably a 30-acre blaze in Baileyville, near the Canadian border. That fire was 20% contained as of Monday, officials said.

The forest service also responded to a half-acre wildfire on Big Island in Sakom Township that was 25% contained by Tuesday night. In Marion Township, a wildfire started by a power line was quickly contained Tuesday, the forest service said.

In response to the uptick in fires, the forest service is increasing staffing, deploying additional wildfire suppression equipment and increasing aviation coverage, which Teller says is valuable both for detecting fires quickly and for transporting crews to remote locations.

PREVENTING FIRES

Fire officials in Skowhegan recently said there has been an uptick in fires at Sappi’s Somerset Mill because of the dry, hot weather this summer. Deputy fire Chief Ryan Johnston said the department has responded to nine or 10 fires at the mill this year, including six or seven since June.

“I attribute maybe 80% of it to the high heat and the lack of rain,” Johnston said Tuesday. “I think that that doesn’t help matters.”

The state Fire Marshal’s Office says it has not yet seen a pattern of building fires related to dry conditions, but local fire officials say there are steps people can take to make sure they don’t spark fires that could spread to buildings.

Best, the Biddeford fire chief, said people should not have campfires and need to be extra cautious to properly dispose of smoking materials.

“Everything is dry,” he said. “If leaves accumulate around houses or in alleyways and someone discards smoking material, fires can get going very quickly around buildings.”

To help prevent wildfires and property damage, officials recommend clearing a 30-foot space around buildings that is free of dead leaves, brush and other flammable materials.

People should also make sure grills, fire pits and chimneys are clear and function properly, and homeowners should consider fire-resistant landscaping.

“If you’re going to have a recreational campfire on your own land, make sure to keep it small, have plenty of water available and never leave it unattended,” said Teller, of the forest service.

Members of the public are also advised to call 911 if they see an out-of-control fire or a concerning amount of smoke in wild areas.

Staff Writers Drew Johnson and Jake Freudberg contributed to this report.