AtmosFear is a mod for S.T.A.L.K.E.R. - Call Of Pripyat that tweaks and expands the vanilla weather system to be more realistic and various.
Awesome modification for a rather unatmospheric game. Adds a whole new feeling that the Zone is real, and not just some bland creation using plain ground textures. Emissions are far more fearsome, and the chemical and radioactive fallouts are entertaining as well. This mod will always keep us asking for more, and undoubtedly AtmosFear 3 will only be better.