Here's a little tip if you're shooting anything with sky in it on black and white film. Fit a yellow filter on your lens. This filter darkens blue, leading to better separation between sky and clouds (thus helping to avoid void-like white skies too). 

Other benefits of a yellow filter include giving better separation to foliage (it lightens green, yellow, orange and red), and, for many, more natural skin tones. Sure, you'll lose a stop of light (the filter shields the light entering the lens by a factor of two, i.e. the same scene needs twice as much exposure). If you are metering through the lens, there is no practical penalty to this, other than that speed loss.

A good addition to the kit of the black and white film photographer.