Cornrows on "white-girl" hair?

Next month, I'm going to a HOT country where I basically won't be able to wash my hair for 3 months. I have EXTREMELY thick hair. Due to the heat AND the fact I won't really be able to wash it, I'm considering getting my hair braided into cornrows and leaving it for 3 months. Does anyone know how this will affect my hair in the long-run? (Severe breakage... hair falling out... braids staying in... etc.)