Kings Canyon National Park closed due to KNP Complex Fire

FRESNO, Calif. (KFSN) -- The KNP complex fire saw substantial growth of nearly 1400 acres overnight, impacting air quality in Central Valley. Just days ago, the historic Sequoia National Park entrance sign was covered with aluminum structure wrap.

Engine after engine is continuing to fight the flames of the KNP Complex Fire, which has now led to the closure of all visitor services and attractions for all of Sequoia and Kings Canyon.

The flames have scorched more than 25,000 acres in less than two weeks, charring trees and leaving parts of the historic park covered in a black landscape.

Officials say the smoky conditions made it impossible to fly any helicopters or airplanes to attack the blaze on Tuesday, but there is an upside to the haze.

"The smoke keeps the humidity up and temperatures down, so it kind of puts a lid on the fire so the activity isn't intense," says KNP Complex Fire PIO Mark Garrett. "If that smoke cleared and we had blue skies, sun and wind on the fire, that is a more challenge for firefighters on the ground, but that also gives helicopters to get in the air and assist those folks. So it is a balance either way."

Officials say the fire intensity was reduced as it moved into areas where prescribed fire treatments were previously completed in the Giant Forest area. That proactive work has helped to protect the iconic sequoia trees.

"If you have a landscape that's healthy and it's been treated over several decades, that fire behavior can be really intense," Garrett said. "But once it meets that footprint of the prescribed burn, the behavior changes, the flame length drops down and it gives firefighters really a chance to really attack it and manage it much more easily."

Information Officer Mark Garrett tells me nearly one thousand personnel from across the country are working this fire, 24 hours a day. Their top priority is protecting lives and infrastructure, followed by the trees.

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"Folks are really happy to be here and be a part of this fire just cuz we are protecting the iconic trees, so I think spirits are high," Garrett said. "We haven't lost any structures. We don't have any injuries. We don't have any sequoias that are burning so all in all, I think we are looking pretty good."

Evacuations are also still in effect for a portion of Three Rivers from Mineral King Drive to the Sequoia National Park Boundary.

Mineral King Road is closed.

At this time, there have been no changes to the evacuation warnings or orders.