Wind gusts up to 60 mph in the fire-ravaged U.S. Pacific Northwest forced firefighters to retreat for safety and helped spark a new blaze Saturday, as fire officials in Washington state and Oregon were hoping for cooler weather to aid containment efforts. Some wildfires, including the Twisp River fire that killed three firefighters in north-central Washington state Aug. 19, were being contained, the Seattle Times reported.

The area’s wind gusts were likely to cause “significant growth” Saturday in the Tunk Block and Lime Belt fires in Washington's Okanogan County, officials said. The wildfires burning there are now the largest in state history, the Times reported.

Firefighters withdrew from the area between the Tunk Block and Lime Belt fires because blowing dust had hampered visibility, Lisa Machnik, a spokeswoman for a fire management team, told the Times. “The decision was made not to put people in the way of the fire with the wind,” she said, adding that despite the weather, “what I’ve heard so far is that containment areas are doing well.”

The Tunk Block fire was expected to merge with another blaze burning to the east, federal fire officials said in a statement. Figures released late Saturday said the fires in Okanogan County had burned 304,782 acres, or 476 square miles, the Times reported. The Twisp River and Nine Mile fires were each about 95 percent contained, while the Tunk Block fire was only 10 percent contained.

Northwest fire officials told U.S. Agriculture Secretary Tom Vilsack on Friday that incoming cooler weather could help calm blazes threatening 14,000 homes in Oregon and Washington. The National Forest Service was spending $10 million a day on fire suppression in the region, the Associated Press reported.

As of Friday, a total of 3,382 fires had burned across the two northwestern states. More than 10,900 firefighters were in the region battling 11 large blazes.