When to Go
October through May is considered to be the best months to travel in Nepal.
Autumn is the best season for trekking as you will have an excellent weather and tantalizing mountain views. January and February are noted for cold weather with occasional snowfall at higher elevations and trekking involving high passes are not operated. Excellent views are plentiful. These months are popular and ideal for trekking for those who are well equipped or who remain at lower elevations below 10,000ft.
Late February brings spring in Nepal and offers exhilarating trekking for those who are interested in flowers, birds and natural grandeur. Different varieties of wild flowers, specially the rhododendrons make the hillside above 8,000ft unforgettable paradise during this season.
April and May are the expedition season and the best time for climbing the high peaks. It is mildly warm at lower elevations but occasional haze mars beautiful view of mountains. At higher elevations over 4,000 meters (13,000ft) the mountain views are excellent and the temperature is quite moderate even at night.
Monsoon begins in mid-June and lasts until mid-September making travel wet, muddy and most difficult with slippery trails. The mountain views may not be at their best as rain clouds and haze obscure the view. These times are blessed for the keen botanist as the entire country becomes enlivened with blossom of flowers and lush vegetation including the higher slopes and valleys.
While rest of the country experience monsoon with constant rainfall, the upper part of the Annapurna Region and central northwestern region such as Manang, Jomsom, Muktinath, Mustang and Upper Dolpo receive the least precipitation as these destinations fall in the rain shadow areas of the Himalaya including most of the Tibetan Plateau. June through September is the best time to travel the above destinations as the high passes are open, snow melted and valleys become alive with wildflowers and wildlife. Also the locals are in the most festive mood and organize their cultural events in these months to enjoy. So, this part of the world is open for trekking.
Climate and Weather
Nepal has 4 seasons:
Spring (Mar - May),
Summer (Jun - Aug),
Autumn (Sep - Nov),
Winter (Dec - Feb).
Nepal’s climate is varied ranging from the sub-tropical Terai to the cool dry temperate and alpine climate in the northern Himalayan ranges. In the Terai, the hottest part of the country, summer temperatures may rise as high as 40°C (104 Fahrenheit). The climate is hot and humid. In the mid mountain region, the summer climate is mild with temperatures around 25°C - 27°C (77-80.6 Fahrenheit).
The winter temperatures range from 7°C to 23°C (44.6-73.4 Fahrenheit) in the Terai and subzero to 12°C (50 Fahrenheit) in the mountain regions and valleys. The northern Himalayan region has an alpine climate. The valley of Kathmandu has a pleasant equable climate with average summer and winter temperatures of 19°C - 27°C (66.2-80.6 Fahrenheit) and 2°C - 12°C (35.6-53.6 Fahrenheit) respectively.