That will depend on the actual scope, but as long as you pick carefully, they should perform well. Most scopes have top-notch optics and housings that are resistant to water and snow. That will ensure you can use them in severe weather conditions. The clarity itself will depend on the optics, and you should also pay attention to their brightness. Some units will perform great in low-light conditions, such as the Burris Fullfield II 3-9x40mm Riflescope, but others might not be able to offer that clarity level. Generally, you should be able to use Marlin 60 scopes in different weather as long as you pick a high-quality model.