Every country occurs the season of the year to know about the climate. Nepal is known as Himalaya kingdom. It has divided into 4 seasons are Autumn, Winter, Spring and Summer.
Autumn
In Nepal, the autumn season is considered as the best trekking and peak climbing season, which customarily refers to the month of September, October, and November. The autumn season exposes excellent weather for stunning views of mountains, landscapes, and valleys. The trails remain without flash flood with arid. This season is characterized by decreasing temperature so at high altitude possible to snowfall.
Winter
It is characterized as having the coldest temperatures of the year in Nepal but clear weather. This season customarily refers to the months of December, January, and February. During this time at a high altitude area the trekking routes are blocked with snow but, below 3500m elevation region also offers great views of mountains. It is considered fewer trekkers do trekking in Nepal.
Spring
The season of the year, which is characterized by increasing temperatures, it customarily refers to the months of March, April, and May. This season exposes green scenery and above 2000m rhododendron and magnolia are blossoming time all over the forests. The spring season is the second busiest trekking season. The world top mountaineers and Everest climbers summit the Mt Everest in this spring season.
Summer (monsoon season)
In Nepal, raining season occurs heavy and torrential rain and it also lingers for a few days. It causes floods, landslides and flash floods. Definitely, it is not ideal to trek in Nepal. Monsoon in Nepal is caused by the Bay of Bengal from the east side and the Middle East from the west side. This season is characterized as having the warmest temperatures of the year. Customarily, this refers to the month of June, July, and August. Nepal has some regions where less raining in especially in upper Dolpo, Humla and Upper Mustang are the best summer trekking routes which remain at a dry and arid atmosphere.