In reply to rft:
It drizzled a bit on my first visit to Harrison's a few weeks ago, but our group's instructor still had us climbing, and the rock was completely dry by the next day. It was very warm and dry there two days ago, so as long as it doesn't rain too much today it should be OK by tomorrow. Maybe.
I'm a noob and I've only been there a few times though, so take this advice with a pinch of salt.
Apparently Bowles dries out quicker than the other crags in the area, as it's a bit more exposed to sun and wind, so if Harrison's is too damp you could try there instead.
Post edited at 12:22