State transportation officials say motorists should avoid travel southwest and central Georgia as cleanup efforts continue in the wake of Hurricane Michael.

Though most state routes are open and passable, fallen trees and other debris are still blocking highways at about 50 locations, and some 150 traffic signals are still dark.

“Motorists in the hardest hit areas are still advised to avoid travel as much as possible, particularly in southwest Georgia,” the Georgia Department of Transportation said Friday. “Motorists and residents should be advised that road conditions are not yet back to normal on many area routes, and residents should not expect routes to be ‘all clear.’”

Hurricane Michael left a trail of destruction across much of Georgia Thursday. Fallen trees and other debris blocked highways in nearly 250 locations and left hundreds of traffic signals dark.

Some 1,400 Georgia Department of Transportation workers have made substantial progress in clearing debris. But it could be several days before all the roadblocks are cleared.

The priority in the hardest-hit areas is to clear a minimum 12-foot-wide path for emergency vehicles. Priority routes include those that provide access to hospitals, trauma centers and other public facilities.

“Motorists who must travel should always be mindful and proceed with caution on all routes even if the road ahead appears to be clear, as there may be remaining debris, blockages or downed power lines,” GDOT said.

The agency said motorists should never drive under a downed power line or attempt to move it from the road. They should treat dark or flashing-red traffic signals as four-way stops.

Motorists should call 511 to report downed trees or other obstructions and should not try to clear roads themselves, GDOT said. They also should not drive around barricades on the road.