Effingham County students will be back in school on Thursday, albeit with a little later start.

With temperatures expected to fall into the upper teens and lower 20s tonight, the start of the school day Thursday will be delayed by two hours for students and staff, according to Superintendent Randy Shearouse.

The concern for local officials is the potential for black ice. The National Weather Service said the frigid temperatures could cause any remaining liquid on the ground to refreeze.

"Black ice is very hard to see and it can be extremely dangerous," said Effingham County Sheriff's Office spokesman David Ehsanipoor. "If motorists hit a patch of black ice, it could cause them to lose control of their vehicle. Black ice is also dangerous for people walking, causing people to slip and fall on sidewalks and in parking lots."