[CRASH] Game Crashes after Champ Select

Sporadically my league will not load in after champ select. The game displays a black screen with only an error saying "Unable to connect to the server. Please check your network connection and attempt to reconnect to your game." (note that the error message appears behind the logo, which does not ever go away. I tried to upload a screenshot, but the board doesn't seem to want it.)

This remains until the game ends (even after restarting and following troubleshooting procedures), when it shows me the leaver screen. It's happened twice to me now, and apparently at random. I don't know any tricks to bring it on.

I have followed the troubleshooting connection suggestions given by riot to no avail. I don't think it's my computer because my brother (who plays on a different computer but the same connection) has the same error, and if I've gotten this error switching to my laptop does nothing to help. This also happens with or without hardwire. I think it's an issue between my internet and Riot's servers (I have Time Warner), but I'm not sure what to do about that. (Also I never got this message playing while I'm at school instead of my parents' house.)

This is incredibly frustrating because there does not seem to be a way to know when this is going to happen, and it's frustrating for both me and my team (especially me since I don't wanna get banned for this).

Anyone have a fix?