Trees are seen downed from overnight storms in west Little Rock in this photo from Entergy Arkansas.

Strong storms knocked out power to tens of thousands of Arkansas customers overnight and resulted in minor injuries at a national park in the state's north, officials said.

For some Arkansas residents, electricity was estimated to return as late as Sunday afternoon, according to Entergy Arkansas’ online outage map.

At the height of the outages around 5:30 a.m., 63,485 Entergy customers were without power in Arkansas, utility spokeswoman Kerri Case said.

By 3:50 p.m., the statewide number had dropped to nearly 37,000. The bulk of the outages — around 28,500 — were concentrated in Pulaski County. Affected areas included portions of west and south Little Rock as well as communities just to the city’s south.

"We’ve called in approximately 300 lineworkers from out of state to work the outages," Case said, noting that they are primarily originating from Louisiana and Texas. Some were set to arrive Saturday afternoon while the remainder would be on-site tomorrow, she added.

The workers were tentatively set to focus their restoration efforts on Russellville, Little Rock and Stuttgart — the cities that Case said suffered the most storm damage.

Entergy has restoration times of noon Sunday in Pulaski County, and says that time “could change as all damage assessments are completed or if other storm activity results in additional outages.”

"Everywhere that we can, we’ve given customers an estimated time of restoration. In some areas, we are not able to give a time estimate yet," Case said.

As the overnight storms traversed Arkansas, they also downed numerous trees and power lines in the state, the National Weather Service said.

Survey teams determined Saturday that storm damage in Pope County was the result of straight-line winds up to 85 mph. In Russellville, the front glass doors of a Fred's discount store were blown in and several trees were uprooted.

Another survey was set for that afternoon in Little Rock.

According to the National Park Service, the Buffalo Point area of the Buffalo National River sustained "extensive damage" to a campground, cabins, a restaurant and trails.

Minor injuries were reported to campers at the north Arkansas site after a storm hit the area around 1 a.m., park spokesman Caven Clark said. Additional information regarding the number of people hurt was not immediately available.

"This entire area is currently being evacuated and will be closed for at least 72 hours to allow for emergency personnel and park staff to assess damage and begin repairs," the park service said in a statement around 9 a.m.

The city of Little Rock said Saturday morning on Twitter that more than 40 workers were clearing trees. Their work was set to continue through 5 p.m., and officials noted that staff would "reassess needs Sunday."

A large electrical transmission tower was also "blown over" in Pulaski County, according to a storm report.

Austin Kellerman, news director at Little Rock NBC station KARK-TV, said on social media that the storms had affected the station's transmission tower and signal. The affiliate was transmitting Saturday on a backup generator.

Little Rock's Hindman Park Golf Course closed Saturday and will remain shuttered until further notice because of debris in the area, the city's Park and Recreation Department said in a statement.

In a travel advisory around 9 a.m., the Arkansas Department of Transportation said a portion of Arkansas 338 south of Little Rock, just west of Interstate 530, was closed because of downed power lines and trees. The 0.2-mile stretch remained closed around 4 p.m.

Extreme heat became the primary weather concern Saturday as crews worked to restore power. A heat advisory, in effect until 7 p.m., encompassed central and southern Arkansas.

Heat index values, which measure how the air feels when humidity is factored in, were forecast to reach between 105 and 110 in those regions, meteorologists said.