Previously, in Dex Takes A Holiday (2009), Frank Lundy is heard recording notes during his encounter with the Trinity killer. He quotes the physical description of the killer as being 200-220 Lbs.
Later, Dexter is listening to the same tape recovered from the evidence room; the playback describes the Trinity killer as being 190-200 Lbs.
At the opening, when the ambulance with Deborah in it leaves the scene of the crime, a member of camera crew is visible behind a car. He's trying to step a bit forward, but remains seen.
When Dexter is following Trinity in his car, you can clearly see a sign that shows Los Angeles is only 31 miles away.