The main thing you will probably need to watch over a hot summer is moisture -- making sure your soil doesn't get too dry. Outside of that, ppl forget that MJ comes from really hot places.. 90-100 is no big deal.
A key thing for that brutal of a summer is strain selection -- personally, if I were in the market for outdoor seeds, I'd check out Mandala seeds. They have a great rep, and continually work in the original land race (ie. original toughness) genetics into their strains. I haven't bought from them personally, but their rep on RIU is pretty air-tight. And if their site info is bullshit, it's some really well-thought out and well-written bullshit.
A lot of indoor strains are heavily inbred, and have a lot of their natural toughness removed thru breeding. They likely won't survive the move from indoor to outdoor, or super high temps..
Good luck..