Nepal, as a tourist destination is good for all seasons, however, the best seasons for trekking and expeditions are Spring and Autumn. The best season for trekking and peak climbing is during Autumn months (Oct - Dec) which are noted for clear weather and excellent views of silvery mountains against blue sky. It gets colder towards the end of December and winter months (January and February) are good for low altitude treks with sunny days and magnificent mountain views.

In early Spring, February and March are ideal months for trekking at moderate altitude with hill sides covered with wild flowers and spectacular display of rhododendron above 1800 meters. March - May are good months for high altitude trekking and peak climbing with excellent mountain views and moderate temperature at higher elevation over 5000 meters. Many of the high mountains are in the rain shadow, so the monsoon season (June - September) is good for trekking in Trans Himalayan areas like Mustang and Dolpo (upper), Mount Kailash - Mansarovar and others.

The season for Himalaya expeditions begins from the middle of March and ends by the end of may in Spring season. For Autumn season, the expeditions begins from end of August and lasts till the end of October. Some expeditions are arranged during Winter season as well which normally begins from November and lasts till the end of December.