Weather and climate in Nepal play a vital role in affecting when traveler come to Nepal to experience natural and man-made heritages of this beautiful country. If you are in the planning stage of your upcoming trip to Nepal then it is important to understand the seasonable variations so that you can select the best time to visit Nepal and experience the activities you want to do. If you come in June / July to trek in Annapurna or in Everest then it won't be a good idea, similarly if you come for climbing in December it won't be an option as well. Nepal has 4 difference seasons in general. Please find some information below about these seasonal variations in Nepal:
[ December, January, February ]
December and January offers clear visibility though high altitude treks can be difficult at this time due to severe cold. If you can endure cold then it is still a good time to do treks in Nepal. The views are generally very clear. The days are dry. The trekking routes are generally peaceful with few people met along the routes. The temperatures are average during the day however falls rapidly in the night. It hardly rains or snows during winter season. The tours are easily doable. Morning and evening are colder. Climbing peaks or mountaineering is not possible in winter season.
[ March, April, May ]
The second best time to visit Nepal, spring season offers amazing views of Nepal. This is end of dry season. Trekking routes are full of trekkers. Popular cities like Kathmandu, Pokhara, Chitwan, Nagarkot, Dhulikhel etc. are full of tourists. The temperature is quite warm in lowland Terai region and average in hilly areas including in the popular trekking areas. Some regions are fully of rhododendron blossoming forests. This season is perfect time for travelers looking to make a visit to Nepal, either for tours, treks, rafting or adventure adventure activities.
[ June, July, August ]
This season is very hot and humid. It's dusty everywhere in Kathmandu. The cities are flooded everywhere when it rains. This is obviously not the best time to visit Nepal. Temperatures in lowland Terai are above 35 degree Celsius where around 30 degree in cities like Kathmandu and Pokhara. Tours are still doable in this time with some rain showers but trekking is not the best. Trekkers still visit Nepal during this time however it's not optimum experience. Trekking routes in lower altitudes are full of leeches. Rafting is generally not doable. Rain occurs during the night most of the time and leaves sky clear in the morning. It starts getting cloudy and blocks the visibility after late morning.
Trekking specially in rain shadow area like Upper Mustang, Upper Dolpo area are best in this season. These areas are situated behind towering Himalayan peaks so experiences less rain.
[ September, October, November ]
Autumn is the highest tourist season in Nepal. Early September still experiences a bit of monsoon though this season is ideal for all type of treks in Nepal. Trekking routes, touristy cities and the rivers are full of travelers. The views are crystal during the whole day means it remains amazing from starting of the walk to conclusion of the trek. Trekking to Everest Base Camp, Annapurna Circuit Trek, Annapurna Sanctuary Trek or Langtang Circuit Trekking; all routes are full of trekkers. The temperature is cool as well as winter season starts after November.