Oslo is 6 hours ahead of Miami
Best overlap: 8:00 AM to 12:00 PM in Miami is 2:00 PM to 6:00 PM in Oslo.
The overlap falls at 8:00 AM to 12:00 PM in Miami, or 2:00 PM to 6:00 PM if you're in Oslo. You've got a decent 4-hour window. Set a recurring time near 8:00 AM in Miami (2:00 PM in Oslo) and stick to it.