Correction: An earlier version of this story referred to the "southbound" Prado Road off-ramp; it's actually a northbound off-ramp.
UPDATE 2:30 p.m. The highway was reported to be fully reopened at 1:03 p.m., according to Caltrans spokesman Jim Shivers.
UPDATE 11:05 a.m.: Highway 101 will be fully closed in both directions at Prado Road this morning as PG&E crews work on a downed power line at Prado Road and Elks Lane.
CHP will initiate two five-minute full closures of the highway so PG&E can remove power lines.
The northbound Prado Road off-ramp is closed; the Prado Road on-ramp remains open.
It is unknown when the highway will be fully reopened.
UPDATE 10:50 a.m.: Power has now been restored to customers in the Prado Road-Elks Lane and South Higuera areas, according to PG&E. Utility crew workers continue to investigate why a power line came down.
Original story: Tom Cuddy of PG&E said 637 customers are without power in San Luis Obispo, including The Tribune's office.
A power wire is down, he said, and a crew is on its way to investigate the problem. He expects the power to be restored shortly.