Cooler weather got you down? Not me (October is actually my favorite month of the year, and Halloween my favorite holiday.) But my wife hates it when summer ends.
Here's something. Check out some Halloween music, and use it as background music while playing your RPG games. The two outfits that seem to be the most well known in this particular ouvre are Midnight Syndicate and Nox Arcana.
There; that's the entire first CD by Nox Arcana, Darklore Manor that someone made as a youtube playlist. Their other CD Blood of the Dragon, with its more overt sword & sorcery theme might be a better fit for most fantasy RPG players, but frankly, I think the Halloweeny sounds work quite well too.
The only thing to watch out for if using Nox Arcana in your games is to eliminate the tracks where Vargo narrates his poetry or other spoken lyrics over a bit of background. That'll probably distracting at the game table. Personally, my favorite Nox CDs would be probably Grimm Tales, Transylvannia and Phantoms of the High Seas, which is a little bit different thematically from the others. Necronomicon is a decent Cthulhu-themed album, although the track "Azathoth" doesn't even have any "infernal piping of blasphemous flutes" which is bizarre. They have a big catalog, but in my experience, the albums mostly start to run together after a while; they're all cut very much from the same cloth. Phantoms and Blood of the Dragon are the most divergent, other than the winter/Christmas ones. Instrumental gothic Christmas music? They actually put that stuff out with a straight face, yeah.
From competitors Midnight Syndicate, I'd vote for Vampyre, Dungeons & Dragons, and maybe Dead Matter--not the movie soundtrack album of that name, but the unrelated studio album with the same title. Yes, the same band put out two albums with the same title but a completely different track list. Confusing. The subtitle for the one I'm recommending specifically is Cemetery Gates. But as with Nox; the albums aren't really all that different from each other, with the possible exception of Dungeons & Dragons and The Rage. It wouldn't hurt you to instead go for "greatest hits" reissues--although neither of their two such albums has my favorite track, "Blackest Rose."