The truck was traveling east on Interstate 580 around 4:30 a.m., just east of the San Quentin off-ramp, at speeds in excess of 45 mph when it was overturned by strong winds, Officer Eric Hohmeister said.
The driver had ignored high wind warning signs when entering the bridge, Hohmeister said.
The empty tractor trailer overturned on its right side, blocking the two left lanes. Tow crews had to wait for winds to subside before attempting to move the fallen vehicle.
The truck was righted and the roadway reopened by about 10:30 a.m.
There were no reports of any injuries and no gasoline was spilled.
Eastbound lanes were blocked for more than five hours, with traffic using the right shoulder to pass.
