San Diego is 9 hours behind Oslo
Best overlap: 5:00 PM to 6:00 PM in Oslo is 8:00 AM to 9:00 AM in San Diego.
Your shared working hours run 5:00 PM to 6:00 PM in Oslo (8:00 AM to 9:00 AM in San Diego). The overlap is tight at roughly 1 hour, so protect it: 5:00 PM in Oslo / 8:00 AM in San Diego is your safest recurring slot.