National Park Service officials closed all facilities in Great Smoky Mountain National Park Tuesday morning due to a wildfire that started on Chimney Top Mountain, the site of one of the park’s most popular trails.

High winds and low relative humidity from Sunday afternoon through Monday helped spread the fire when falling trees downed power lines, according to a post on the park’s Facebook page. Helicopter water-drops and other firefighting efforts on Sunday did little to stifle the flames.

On Monday morning, the Park Service closed US Highway 441, which runs through the park. Nineteen trails, eight campsites, and the shelters on Mt. LeConte and Mt. Collins were also closed due to fire on Monday.

Weather conditions, including wind gusts that reached over 80 miles per hour, contributed to spreading the fire in a state stricken by drought since May. The U.S. Drought Monitor shows that Tennessee’s Sevier County, where the park is located, was in extreme and exceptional drought on November 22. Parts of Tennessee, the Carolinas, Georgia, and Alabama are also experiencing long-term extreme drought, per data from the NOAA.

Authorities have been watching the fire situation for a few weeks. The Tennessee Emergency Management Agency (TEMA) declared a state of emergency for drought and wildfire threats on November 10, and the park issued a ban on campfires and open grills on November 15 because of dry conditions and fires in the region.

Thousands evacuated the nearby cities of Gatlinburg and Pigeon Forge as the fire spread beyond the park Monday evening, according to a TEMA statement from Tuesday morning. Four people have been reported injured, but no deaths. The weather forecast predicts rain and lower winds this afternoon and evening. But even with rain currently falling, TEMA said, “the fires continue to burn and structures remain engulfed, with little hope that the rainfall will bring immediate relief.”