There will be a total lunar eclipse beginning about 1:15 am EST. Totality will begin at 2:41 am EST and last for 72 minutes, with the moon in deepest shadow at 3:17 am EST. The eclipse will be visible throughout North America. The last time there was a total lunar eclipse during the solstice was 21 December 1638, and the next one will be 21 December 2094, so unless you’re very young and very lucky, this is your one chance.
In the Northern hemisphere, tonight is the longest night of the year. Thanks to the eclipse it should be the darkest, so you should also be able to see the Ursids meteor shower. Look in the direction of the Little Dipper.
For more information about the eclipse, see NASA: Solstice Lunar Eclipse.