Great idea - I've got a Nikonos V! I never get a chance to use it - may have to squeeze it in!
I use my Nikonos V all the time in bad weather. And in good weather if what I am doing may be hazardous to the health of regular cameras.
I shot this with my Nikonos V, the 35mm lens and Fuji Provia 400 two weeks or so ago. As Fstop mentioned, dreary weather is a fantastic time to use colour film. The colour saturation provides contrast and subject isolation that may be lost in a sea of grays in poor weather. Then again, it of course depends on what look you are going for.
Anyway, take the Nikonos! They rock.