ENCINO (CBS) — The northbound lanes of the 405 Freeway in the Sepulveda Pass are expected to be closed starting at 11 p.m. Saturday to allow contractors to remove and replace old overhead freeway signs, Metro officials announced.

Closure of the northbound lanes on the 405 in the middle of the pass will start at 11 p.m. Saturday with the entire northbound 405 closed by 1 a.m. Sunday. The barricades are supposed to be cleared by 7 a.m.

Early morning traffic is expected to be detoured onto Sepulveda Boulevard through the old tunnel and into the valley. Detoured traffic will be able to re-enter the freeway near Ventura Boulevard, Metro officials said.

The northbound on-ramps at Getty Center and Mulholland drives will be closed during that period as well. Metro officials do not expected southbound traffic to be substantively affected.

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