The closure stretches from Cesar Chavez Street to 17th Street and begins at 11 p.m. Friday. All northbound lanes are scheduled to reopen by 6 a.m. Monday. Southbound Highway 101 will remain open.
Caltrans is urging northbound drivers to use Interstate 280 as a detour or consider public transportation. The closure could also impact travelers coming into San Francisco from the Peninsula and San Francisco International Airport.
Despite the holiday weekend, Caltrans says its traffic data show fewer vehicles typically head into San Francisco over Labor Day compared with a normal weekend.
"From experience of the Labor Day closures, we've seen a decrease in traffic coming into the city," Caltrans District 4 spokesperson Pedro Quintana said. "So that is the reason why we are strategically planning this weekend."
The closure is part of Caltrans' ongoing rehabilitation of Highway 101 through Hospital Curve. The roughly 70-year-old roadway is reaching the end of its service life.
Crews will work around the clock this weekend to remove aging concrete from the two right northbound lanes and replace it with continuous reinforced concrete pavement designed to last about 40 years.
"There's never a good time to close a major freeway like U.S. 101," Quintana said. "But we have to get this work done."
Caltrans says completing the work during a full weekend closure will significantly reduce the amount of overnight construction needed later.
This will not be the last full closure. All northbound lanes through Hospital Curve are scheduled to close again from 11 p.m. Sept. 18 to 6 a.m. Sept. 21 as crews continue pavement repairs.
The work is part of a larger rehabilitation project covering 15.4 lane miles of Highway 101 between the Candlestick Point area and the Mission District. The project also includes drainage and median barrier improvements and is expected to continue into 2028.