At 8:16 pm on July 4th, 2020, a moon 99.9% full will rise in Boston just before sunset (8:24 pm).
July 2020’s full moon, also known as the “buck moon,” will be the first full moon of summer 2020. It is named, according to the Farmers’ Almanac, for the new antlers seen on young male deer at this time of year. July’s full moon is also known as the thunder moon, hay moon, or wort moon.
The moon technically won’t reach peak fullness until 12:44 am EDT on July 5, but it will appear full when it rises at 8:16 pm Saturday.
There is also a partial penumbral lunar eclipse the same night, visible to North America. The eclipse will begin at 11:07 pm EDT July 4th, reach maximum just before 12:30 am, and end at 1:52 am. About 1/3 of the moon will be covered by the earth’s "penumbral" shadow.
The moon rises in the east, so you're going to want to look that way. If you're trying to grab photos, go somewhere facing east with a picturesque foreground. Two well-known spots to watch a Boston moonrise are North Point Park in Cambridge and the BU Bridge on the Boston/Cambridge line.