The Hess Creek Fire is the largest fire burning in the country. The fire, which started on June 21 when it was sparked by a lightning strike, is over 159,000 acres, crossing an Alaska highway and has yet to be contained.

A Hess Creek Fire progression map as seen on July 12 shows how the fire has grown in size over the last several days.

Two spot fires crossed the Elliott Highway on Tuesday causing hazardous, burning trees to fall across the highway, according to AK Fire Info. Additional resources arrived Thursday evening after the fire grew five more acres before firefighters finished constructing a line to keep it from spreading further along the highway.

The fire continued to burn down the south side of Amy Dome through a forest along the southeast corner before it crossed the Tolovana River. The fire is approximately seven miles northeast of the Elliott Highway, which is within several miles of the Colorado Creek Trailhead.

Anyone driving in the area should use caution and drive slowly between mileposts 62 and 66.

Any firefighters who were not focused on these hot spots diverted their efforts on monitoring fire activity near some cabins directly in the line of the fire.

Heavy smoke has continued to be a problem for firefighters attacking the massive fire, hindering visibility. According to AK Fire Info, the Idaho team in command of the fire had to move their incident command post nine miles up the road on the highway.

“Smoke continues to be problematic for our crews,” said Andrew Addey, the incident commander. “We felt moving the ICP to an area not as heavily impacted by smoke would provide some minor relief to firefighters when they come in to sleep after their operational period.”There was such an abundance of smoke in Fairbanks and at the Hess Creek Fire site, it prevented a helicopter from flying on Thursday as well, the update from AK Fire info stated. In addition to smoke concerns, a red flag warning is still in effect through Friday until midnight because of the chance for numerous lightning strikes.

Fire behavior and weather

An incident report for the fire says a mixing of thermal troughs over the fire could produce showers and thunderstorms over the next few days. This weather will likely change wind direction, with winds switching from the northeast to southwest. This should hopefully push the fire back into itself and stop it from spreading. The slightly cooler temperatures and continued inversion over the fire should help reduce fire activity.

Public awareness

Smoke is being forecasted as “unhealthy” for the next few days, according to the Air Quality Index map. Any residents affected by smoke can go to the Fairbanks Memorial Hospital where they created a 24-hour smoke respite center, located at 1650 Cowles Street inside the Chandler Room in Fairbanks. People are encouraged to reduce their exposure to smoke by staying indoors with the windows closed. Visibility will remain limited as the fire continues to spread further south, anyone wanting the latest road conditions can check the Alaska Department of Transportation website.

AQI map for July 12 shows

Earlier this week, the blaze advanced toward the community of Livengood, where an inversion has trapped smoke in the area and surrounding valleys after the fire's massive growth. Firefighters focused efforts on conducting burnout operations, slowing the fire's progression.

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