Climatic conditions vary from one region to another based on their geographical features. Generally, Nepal has five seasons: spring, summer, monsoon, autumn, and winter. The climate ranges from tropical to arctic depending on the altitudinal variations.

The Terai region that lies in the tropical southern part of the country has a hot and humid climate. The mid-land or hilly region has pleasant climate all round the year but the winter morning and nights are cold. The Himalayan region has a considerably cold alpine climate. The Himalayas hinders cold winds from Central Asia in the winter and forms the northern boundary of monsoon wind patterns. Eighty percent of the rainfall is received during the monsoon (June-September). Winter rains are more pronounced in the western hills. The average annual rainfall is 1,600 mm, but it varies by eco-climatic zones, such as 3,345 mm in Pokhara and below 300 mm in Mustang.

There is no seasonal restraint to travel in and through Nepal. Even during the December and January, when the winter is relentless, there are atoning bright sun and stunning views. Noting all the trekking areas in Nepal, the best time to visit Nepal is during spring and autumn. Spring brings the pleasant weather along with the new blossoms and after the monsoon, there is the clearest sky.