Did you ever watch the TV show, Get Smart? The lead character, Maxwell Smart, went through a number of doors on his way into the office. Although it wasn't the goal, having to pause, breathe, and walk gives him time to compose himself.
How you walk into your office sets the tone for the day. If you walk in frazzled, even due to non-work related events, the team feels frazzled. If you walk in calmly, they feel calmer.
Take a moment in the parking garage, the elevator, or the hallway to compose yourself and set the right tone for the day.
In case you've never seen the show, here's a clip.