As you are probably aware, the upcoming eclipse is not a short event.
The phenomenon actually takes place over the course of around 3 hours, so it couldn't hurt to narrow down your watching time.
This handy calculator will tell you exactly when you should be watching, according to your zip code, and what percent of the totality you can expect.
I, for example, live in Owens Crossroads and am going to get the best view at 1:31pm.
This is the special report Dan was so excited about, from the eclipse in 1970.
It uses a really great graphic to explain why we don't get one eclipse a month.