Update 3:52 p.m.:
Expect residual delays on US-101 northbound at Peninsula Avenue in San Mateo after two lanes were shut down at 1:44 p.m. Saturday due to an accident and potholes. All lanes are now open.
On Saturday at 1:44 p.m., a severe traffic alert went into effect on northbound US-101 at Peninsula Avenue in San Mateo County.
The two right lanes are closed due to an accident and potholes.
Motorists are advised to expect delays and to use alternate routes. There is no estimated time of opening.
Patch will update this story as more information becomes available.