In my experience, from about now until "winter" hits...You really have to be ready for anything. Good footwear, water,wind resistance for legs and upper body. Warm layers. A good hat. Just put yourself in the place of the climbers that got stormed on last season. What gear made their survival possible. Even though me pack is almost always a bit heavier then my climbing partners, I KNOW i will make it through that unplanned bivy.
I hve been out on blue bird days and have been hammered by the weather. The flip side to that coin is stormy conditions that never really turned "full on."
October is one of my favorite months to climb. Empty trails, no bugs, cool temps...But...Winters on it way. For real!
Tad