Like many things photographic, compromise may be necessary. Environmental sealing (both lens(es) and body) is obviously a good thing if you can afford it, but it is most often found on premium bodies and lenses, not the more affordable models. Reviews of particular products often comment on weather and dust sealing, so do a bit of internet research. Others will know more about the D7000 than I.
But there are also some quick, cheap and light solutions for rain, like carrying a clear plastic shower cap to put over the top of the camera and lens (but not covering the end of the lens unless you are going for the vaseline look
), or a ziploc bag. Both of these allow you to manipulate controls reasonably well while keeping most of the rain off. Not so good for heavy rain of course. I always carry a small towel or at least a dry shirt in reserve in case I have to do a real drying off of some gear. A small nylon tent fly draped over your tripod is another solution (llike those dark cloths used in 19th century photography) until the moment you press the shutter.
Actually I think extreme cold can be more of a problem than rain, because if you bring a cold object inside a warm humid environment, condensation will do damage internally as well as externally. If you are bringing a camera in from the cold, wrap it (or your whole camera bag) tightly in a plastic bag before bringing it inside, and only take it out of the plastic once it has warmed up.
The payoff for all this trouble is that often the best landscape photographs are taken in difficult conditions. Persevere.