SPOKANE, Wash. -

Firefighters are fighting both difficult terrain and a still very active fire though now, two days since its start, crews are on the cusp of gaining the upper hand against the Yale Road Fire.

Burning in southern Spokane County, the Yale Road Fire is still very active, with terrain making things more challenging for firefighters battling flames in canyons and heavy timber.

"A challenging fire, certainly not insurmountable, but will take time," Washington State Patrol Trooper Jeff Sevigney said.

More than 550 firefighters are now fighting the fire. Helicopters worked the Hangman Creek area Tuesday morning while farmers worked nearby to protect their crops.

The fire has burned approximately 3,500 acres, revised downward from an earlier projection of 4,000 acres, and 10 homes. Level 3 evacuations remain in place on the fire.

The crews are getting an assist from the weather, with a combination of cooler temperatures, diminished winds and higher relative humidity helping crews gain the upper hand on the fire lines, where firefighters are working to keep the fire within its existing footprint.

Containment is at zero but the efforts from fire crews and volunteers working to save their properties are making a difference and there could be some measure of containment on the Yale Road Fire as soon as Tuesday evening.