Direct sun isn't bad as long as it isn't scorching. Some morning or late sun isn't bad, but you have to acclimate it so it is used to it. Meaning give it half an hour of direct sun one day, add another 15min the next, and so on. I just find it easier to give it full indirect sun (north) and it gets a peek of sunset light so it's not to0 hot. If there's a sudden heat wave, give it a break and move it a foot back from the window. Think of it this way: if you stuck your arm in the window would ya burn quickly? If I'm not going outside to hang out, I don't think my VFT would like it, either.
Let's see, I was in Mountain View the other summer with my VFT, I had it in the southern facing window but it was shaded with half closed mini-blind slats. Didn't get any direct sun any other way. Really depends on your home/windowsill.
You should have not problems with humidity in your area, anytime of the year. The water advice is probably the most important. Oh, and keep in mind dormancy come november/december.