More than a week after it started, it is only 17% contained.
Already, several fire departments across the Central Valley have deployed crews to support the fire fight.
Since igniting on Saturday, August 8th, the wildfire has prompted widespread evacuations.
"The latest update from the incident today was a little over 500 homes that were threatened," said Battalion Chief Matthew Mosely of Cal Fire's Fresno-Kings unit on Sunday.
Mosely says it's unclear if any homes have burned.
The Fresno-Kings firefighters deployed to Monterey County on Tuesday.
They are helping with handlines, putting out hotspots, and engaging in direct fire attack.
But they are just a small part of this major firefighting operation with over 2,000 personnel currently assigned to the wildfire.
That includes a Rescue Air Mobility Squad, or "RAMS" team, from Merced City Fire.
As crews risk their lives to keep residents safe, members of the specialized technical rescue team are risking theirs to protect their fellow firefighters.
"They are specifically dedicated to the incident for the rescue of any downed firefighter in a remote area," said Merced Fire Department Chief Casey Wilson.
Four people, including a paramedic, deployed with the RAMS team on Thursday, with two pickups and a UTV, which helps them access very remote areas of the fire.
Madera City Fire also reported sending an engine to battle the Timber Fire.
And back in Fresno County, Cal Fire officials are preparing in case they need to deploy additional crews.
Kerry Mannix is a general assignment reporter for ABC30 Action News. For news updates, follow her on Instagram.