As 13 wildfires ripped across Arkansas on Friday, state forestry pilot Jacob Thomas Harrell took a small plane out to look for additional hot spots.
Late Saturday, search crews still had not found any sign of either Harrell or the single-engine Cessna 210 Centurion since his last radio call more than 30 hours earlier.
"We are going to be here until we find Jake," State Forester Joe Fox said in a statement released Saturday evening. "Tonight and tomorrow's efforts are already planned and we are aggressively covering as much ground as quickly and safely as possible."
Two planes, a helicopter and a number of people from state, local and federal agencies have been involved in the nonstop search, the Arkansas Forestry Commission said. But low visibility hampered the aerial search Saturday.
Commission spokeswoman Adriane Barnes said officials pulled data from AT&T to find the last cell towers Harrell's cellphone communicated with and then searched those areas. Authorities continued to monitor the phone to see if it would pop back online.
"We are exhausting all efforts, especially before bad weather moves in," Barnes told the Los Angeles Times on Saturday night. "He has literally disappeared in one of the most steep, untamed and unreachable areas in terms of creekbeds, ravines and pine trees in the whole state."
Barnes said no drones were assisting in the efforts, but the helicopter does have access to night-vision capability.
Harrell, 34, an eight-year veteran of the air detection unit, was flying a route that he had followed "many times," the commission said in one of several social media updates chronicling the search.
The area's weather forecast Sunday includes rain and hail.
Harrell, who officials said works full-time for the North Little Rock Police Department, has also served overseas with the Arkansas Air National Guard 188th Fighter Wing. He's been a certified pilot since at least 2001 and became a flight instructor more recently, according to FAA records.
Friends sought prayers for Harrell's safe return on Saturday.
"Praying for our family friend, missing pilot Jake Harrell. Please join our family and friends in praying he will be found soon," Tena Decanter Furnish, a spokeswoman for the state's Civil Air Patrol posted on Twitter.
"Please continue to pray for the safe return home of my friend, Jake Harrell -- pilot whose plane went down yesterday and is still missing," @BrianDollar1 said on Twitter.
Low humidity and high winds contributed to heavy fire danger in Arkansas on Friday, threatening at least 15 homes and burning more than 200 acres. Burn bans and high fire dangers were still in place Saturday across most of the state.