Hot, dry and windy conditions are fueling a fast-moving wildfire in Utah, forcing the governor to declare an emergency and restrict fireworks as critical weather across the West gives way to mounting concerns that anything could cause a spark. Firefighters are facing more challenges on the ground from what fire managers and experts call unprecedented conditions. Air tankers and helicopters were grounded Friday as winds picked up on the Cottonwood Fire, the largest blaze currently burning in the U.S. Gusts were clocked at 45 miles per hour (72 km/h) and humidity levels were in the single digits, leaving crews with few options for slowing the flames, especially as they raced through the treetops.“We are not expecting the weather to be kind to us for the next couple of days,” said Alyssa Mason, a spokesperson assigned to the fire. “We are seeing extreme fire behavior out there with some crown runs and definitely some spotting.”

Burning in a sparsely populated area of southern Utah, the Cottonwood Fire ballooned Friday to more than 112 square miles (290 square kilometers). One of several large wildfires burning in Utah, it severely damaged the Eagle Point ski resort in Beaver County and forced evacuations. In the community of Marysvale, the smoke blocked out the sun Friday as ash rained down.