I agree with Tim, manual is the way to go for this, and to start off spot meter the sky at +1 to +2 stops and chimp a few shots from there. If you're lucky enough to have a clear blue sky you'll be about +1 and get
shots like these. If it's a hazy day it'll be tough no matter the exposure. It doesn't hurt to be late in the day such as my examples. AE on such shots is hazardous at best.
- DL