Both of my kids attended different astrophysics sections of SSP (mentioned above) a few years ago; great program that I would highly recommend. This past summer, SSP offered Astrophysics at three sites: UNC Chapel Hill, Univesity of Colorado Boulder, and New Mexico State.
Yale also offers a program somewhat similar to SSP founded by a former SSP instructor called YSPA (more info here: https://yspa.yale.edu/).
Both programs include an observational astronomy component.
Both are also highly selective so you should definitely have backup plans for the summer.