UPDATE [9:55 a.m. Tuesday]: I-75 express lanes through Cherokee and Cobb counties are now open, according to the state authority that manages the system. They had been closed since Monday night.

“Motorists are advised to expect delays and exercise caution while driving on the roadways,” State Road and Tollway Authority spokeswoman Jodi Scott told AJC.com.

UPDATE [6:46 a.m. Tuesday]: I-75 express lanes through Clayton and Henry counties reopened Tuesday morning after they were shut down Monday due to the threat of black ice, according to the state authority that manages the system.

However, express lanes that run through Cherokee and Cobb counties remain closed “for now as inspection for black ice continues,” State Road and Tollway Authority spokeswoman Jodi Scott told AJC.com.

ORIGINAL STORY: Because of the threat of possible black ice, the NW Express Lanes and the I-75 South Metro Express Lanes will close in both directions at 11 p.m., authorities said.

The State Road and Tollway Authorities told the WSB 24-hour Traffic Center about the closure.

It’s unclear whether the lanes will remain closed Tuesday morning during the morning commute. AJC.com has reached out to SRTA for more information and hasn’t heard back yet.

The Georgia Department of Transportation spokeswoman Natalie Dale said, “During inclement weather and poor road conditions, our priorities are to focus our treatment on general purpose lanes to keep them passable and safe for necessary travel.”

The possibility of black ice has prompted most metro Atlanta city and county governments, school districts and universities to delay opening Tuesday morning. Some school districts cancelled school.

For the complete list of schools and offices in metro Atlanta that will delay opening Tuesday morning, click here.

— Please return to AJC.com for updates.

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