redirect if logged in?

hi im the main site techie at lasuni love and were currently in the process of creating a html landing page, we only want the landing page for people who arent registered or logged in, is there a way to directly put the people who are already logged in to the forums directly to the forum and not go to the landing page unless they have logged out. here is current plan for our page it kinda seems unprofessional to have the forum there if your already logged on and have to click it every time you want to go back to the site, is it necessary no, but it would be really nice.

my sketch:


thanks in advance.