It's going to be really hard waiting 30 years before I can talk to you about everything that's happened in the past few days.
7 seconds sound clip from the Back to the Future movie soundboard.
You can hear this line at 01:14:58 in the Blu-ray version of the movie.
Quote context
[...]
- Are you sure about this storm?
- Since when can weathermen predict the weather, let alone the future?
- You know, Marty, I'm going to be very sad to see you go.
- You've really made a difference in my life. You've given me something to shoot for.
- I'm really going to miss you, Marty.
- I'm really going to miss you.
- No! Marty! We've already agreed that having information about the future can be extremely dangerous.
- Even if your intentions are good, it can backfire drastically.
[...]