For a tiny Landlocked country, Nepal has vast geographical diversity. It has pleasant moist springs, hot wet summers, fantastic mostly clear autumns, and cool clear winters. Every season has distinct attractions to offer trekkers. Trekking and other adventure activities are possible any time of the year depending on where you are going. The best time for trekking is after fall and after the winter.
Spring Trekking Season in Nepal (March-April-May)
Spring season is the second biggest trekking season in Nepal. It is definitely less crowded but still a great time to do trekking in Nepal Himalayas. The spring season offers varieties of wildflowers blossoming above 3,000m, especially magnificent views of rhododendrons and Magnolia and the forest grows ever higher, painting the rhododendron hillsides like paradise. The spring trekking season makes higher-altitude trekking more comfortable and exciting. In spring temperatures are mildly warm at lower elevations and there is still quite a moderate temperature at higher elevations over 4,000m, which provides spectacular and excellent mountain views. The afternoons are great for reading and relaxing and just when you begin to worry about tomorrow, the evenings turn sparklingly clear. March and April are often drier than May, but May has the advantage of more alpine flowers. Poon Hill Trek, Mohare Danda Trek, Langtang Gosaikunda Pass Trek, Khopra Danda Trek, Kanchenjunga Base Camp Trek, Manaslu Circuit Trek, Everest Three Passes Trek, Everest Base Camp Trek, etc. are best to do in the Spring season in Nepal.
Monsoon (summer) Trek Season in Nepal (June-July-August-September)
The monsoon (summer) season in Nepal usually takes place from the end of May to early June. However, according to the Meteorological Forecasting Division of the Department of Hydrology and Meteorology, the monsoon season is active from the 13th of June and ends on the 23rd of September. But due to the global warming effect, the climate is not ordered to cycle, it is changing every year. These are a blessed time for keen botanists as the higher valleys and meadows blossom with flowers and lush vegetation all over. At low altitudes in late May and early June, the heat stifles, and clouds billow ever higher cumulating in crescendos of rain. The downpours are usually brief leaving plenty of time to admire the forces of nature. Kathmandu is sticky, humid, and alive. In the Terai, elephants rather than jeeps are used for crossing the swollen rivers. The jungle is lush, vibrant, and tropical. In the high rain-shadow areas, it is surprisingly pleasant, with only occasional showers. It is a time for wandering among the flower carpets and vivid colors while the locals are absorbed in the traditional cycles of agriculture. In monsoon, season clouds billow ever higher cumulating in increases of rain. June, July, and August months are the main rainy months in Nepal and have monsoons with heavy rainfall which makes trekking unfavorable wet, and warm. Monsoon season is the ideal time for trekking and tours to Tibet and Bhutan. However, some regions of Nepal which are connected to Tibet can trek. Nepal Mother House offers treks to the rain shadow areas of Upper Mustang, Nar-Phu Valley, and Upper Dolpo regions which are best conducted in the summer season. Likewise, a short trek with no risk of landslide and flood is also recommended for you during monsoon. Annapurna Short Trek visits Ghorepani poon Hill, Dhampus Sarangkot, Nagarkot Dhulikhel Trek, Helambu Trek, Everest View Trek, Everest Base camp Trek By Road, and Gokyo Lakes trek is also worth doing during the monsoon. Summer season is also the best season to trek behind the Himalayas rain shadow area. Insect repellent is a nice addition to bring!
Autumn- the Best Trekking Season in Nepal (Mid- September to early December)
The autumn season is the one of best trekking seasons in Nepal due to the clear skies, incredible fine weather, and tantalizing mountain views. This trekking season (autumn) starts from the middle of September to late November. This season is the best time for any kind of outdoor activities, cultural and adventure treks in areas such as Dhaulagiri, Manaslu, Ganesh Himal, Kanchanjunga high passes, and other teahouse treks. At this time the whole country changes from a lush, verdant green into harvest colors. These long periods of exceptional weather are occasionally broken for a day or two by a front sweeping overhead causing high cloud or cloud banks that roll up the valleys, and then usually clear out with the sunset. The odd stronger fronts can bring a spot of wet weather as well but it is impossible to tell (even the locals can't) whether a front contains rain. Barring unusual conditions during this trekking season, perhaps two or three periods of showers and drizzle, or short-lived snow at high altitudes can be expected. In an odd year, there is a perpetual high cloud and less than crystal clear sky. In the low country, evenings are balmy while in the middle hills, they are pleasantly chilly. Above the tree line (4000m) nights are sharp and below freezing. Likewise, this is the best time to observe Nepalese biggest festival "Dashain" which falls in October, fifteen days later "Tihar/Dipawali" festivals celebrate all over the country and Chhath celebrate in the Tarai region. September, October, November, and December are known as festivals season in Nepal. The early morning sun is particularly welcomed. Nepal Mother House Treks offers trekking to any part of Nepal and expeditions to any climbing peaks during this time. During this trekking season, temperatures are moderate, making it the best time for any trek or rafting, tour. Since most people plan to go trekking during this season, so we advise you to make early reservations. Most trekkers visit Everest Base Camp Trek, EBC Chola Pass Trek, Everest 3 Passes Trek, Renjola Pass Trek, Manaslu Circuit Trek, Gosikunda Lake Trek, Tsum Valley Trek, Annapurna Bases Camp Trek, Langtang Valley Trek, Kanchenjunga Circuit Trek, Makalu Base camp trek.
Winter Trekking Season in Nepal (December, January, and February)
December to February is known as the winter season. It is noted for occasional snowfall at higher elevations with risky winds and colder temperatures. Generally in winter, the days are clear but morning and evening time will be foggy and cloudy. At night time the temperature will drop below freezing and the stars have that crystal twinkle in the sky. During the winter season, the high mountain passes will be snowbound. If you have a holiday during wintertime and are looking for incredible scenery with fewer crowds, this is an ideal time to go trekking at lower elevations. During this season, we generally recommend trekking below 3500 meters such as Ghorepani Poon Hill Trek, Dhampus Sarangkot Trek, Chisapani Nagarkot Trek, Helambu Trek, Sacred Tsum Valley Trek, and the Langtang Valley Trek. However, it is best to visit Mount Everest Base Camp Trek in December too. The trail to the EBC trek is not at risk during winter and heavy snowfall due to no need to cross the pass to get in. Celebrating Christmas and New Year in the Nepali Himalayas with a pleasant trek is a great way to spend the winter.
In inclusion, visiting Nepal is categorized into various sections, however, it can be said that "Nepal for all Seasons" is due to its geographical diversity and culturally rich, which is suitable for each and every trekker during different seasons. Yes! You can visit Nepal whole in all year round for the different tests.