Leon, you use of a staining dev like pyrocat (which I know you use) will help enormously if you get hot scintilations or whatever they are called. From experience in full sun in Spain and South Africa on small rocks, logs etc these devs really help to hold things within an easily printable (or burnable) range. You will have good margin for error with local overexposure etc with these devs, which you will be thankful for if you get shaded wnow and sunlit etc. Personally I dont just meter one area, I would meter a few areas of snow therefore getting a fuller idea of the range to be meshed with the neg, but I am sure you would do this anyway. You'll have no problems.