Firefighters battling the Oregon Flat Fire, which has so far torched nearly 22,000 acres, could face setbacks if the latest weather conditions shift, officials cautioned Monday. The raging blaze, which is only 5% contained, has destroyed homes and buildings. Thousands of families have been forced to evacuate.

Ten structures — including four homes — have been destroyed by a wildfire sweeping through central Oregon, where thousands of residents remained under evacuation orders on Monday, while a blaze in Northern California wine country has so far spared some of the state’s most famous vineyards.

Four homes have been lost to the Flat Fire as it continues to threaten nearly 4,000 homes in Deschutes and Jefferson counties.