The climate in Scotland tends to be varied because it is surrounded by sea. It can be described as temperate and oceanic, and is characterized by its humidity because it is tempered by the Gulf Stream that comes from Atlantic Ocean. Its winters are mild, they have no comparison with the winters of cities with similar latitude such as Oslo or Moscow.
But do not trust, you will need to wear clothes to protect you from the rain, since it usually rains all year. Snowfall is very normal in the Highlands so wear warm clothes if you intend to get there.
We recommend visiting Scotland in the months of July and August since the average temperature ranges between 15 and 22 ° C, since in winter the average usually drops to 5 ° C.