Nepal is a country with significant variants of geographical features and regions. With a range of 60 m to 8848 m above the sea level in altitude, there is a great variety of climates and weathers in Nepal. Nepal is located in subtropical latitude constituting for its variations in climates. Throughout the year, the climates of different regions vary according to the altitude and seasons.
The climate of Nepal is split into five climatic areas: the tropical and subtropical zone below 1,200 meters above sea level, the cool, temperate zone between 1,200 and 2,400 meters above sea level; the cold zone between 2,400 and 3,600 meters above sea level; the subarctic climate zone between 3,600 and 4,400 meters above sea level and the Arctic area above 4,400 meters above sea level.
The northern Himalayas not only symbolize unique climatic conditions, but they also play a significant part in studying the overall environment of Nepal. The Himalayas function as a barrier to the cold winds blowing in winter from Central Asia, forming the southern limit of the patterns of monsoon wind. The Sub-arctic and Arctic climate zones fall in the Himalayan region of Nepal. Most of the Himalayas are uninhabitable because of the extreme climatic conditions, especially during the winters. The summers are usually temperate in the lower parts of this region while the winters can go below sub-zero.
The Hill Region of Nepal consists of the temperate and the sub-tropical climate zones. This region is considered the most suitable for habitat because of the mild climate. The midlands are pleasant throughout the year. However, the mornings and nights are quite chilly. With average summer and winter temperatures of 19 °, C – 35 ° C and 2 ° C – 12 ° C respectively, the Kathmandu Valley has a more rich spectrum of climate. The Pokhara Valley in this region has the highest amount of rainfall all over the country with the encounter of monsoon winds with the Annapurna range.
The Terai region of Nepal lies in the southern part of the country. It is known for its tropical and humid weather. The summer temperatures in some areas exceed 37 ° C and the winter temperatures range from 7 ° C to 23 ° C in the Terai region of Nepal. Rainfall is widespread in the eastern part of the Tarai (which in Biratnagar receives from 70 to 75 inches [1.800 to 1.900 millimetres] per year), but the western part of Nepal (wherein Mahendranagar fall from 30 to 35 inches per year) is drier. Besides this, this region has also fallen victim to different natural disasters like floods and the Loo (a hot and dry summer wind) several times.
The Monsoon season in Nepal starts from June and lasts until about mid-September. In this season, it is most likely to rain all day. The mornings and evenings are also generally cloudy. The significant rainfall during the monsoon season is during July and August. Eighty per cent of the total rain in Nepal is during this season. Moreover, the weather in the mountain region during this season is highly unpredictable. Most of the views are likely to be blocked by fogs and clouds. However, the occasional cloud parts and sunlight give the most beautiful views of the mountains. The forests also become lush and green during this season, making it a delightful sight for the eyes. If you are planning to trek the higher hills and mountains of Nepal during this time, it can be quite the challenge, but it also offers an experience of a lifetime.
The autumn season is one of the most pleasant seasons for travel and trekking in Nepal. This season starts from September and lasts until November. The skies are clear in this season and the days are warm but not too hot. Autumn season offers the best views of mountains and hills and the abundance of scenarios in Nepal. The temperatures range at about 25 degree Celsius on the days and about 10 degree Celsius at night. However, in the higher elevations, it is already freezing during this time of year.
The winter season in Nepal lasts from December to February. The days are chilly in lowlands and mountainous areas, but in the elevated Himalayas, it is much less temperature. The days are bright, except sometimes. The winter season provides the best view of the snow-capped mountains as the skies are clear. This season is much drier than others, but winter monsoon is a possibility in the western parts of Nepal. At the higher elevation, and sometimes at the lower altitude of 2500 m, heavy snowfalls will occur. The coldest months are January and February. This season can prove to be very adventurous for travel and trekking. However, it requires a lot of preparation due to the extreme climates in the Himalayas.
The spring season in Nepal is another perfect season for travel and trekking. Especially in the Himalayas, the scenario of the fully bloomed Rhododendron forests is exquisite. The mornings are bright and refreshing in this season. Occasional rainfall and thundering is, however, a possibility. The spring season has the most beautiful views with colorful flowers and greenery all around. This season doesn't encounter much snow, making the Himalaya trails easier.
Travelling in and through Nepal is not subject to seasonal constraints. Even in December and January, when winter is at its worst, bright sun and beautiful views compensate for the cold. Like most trekking fields in Nepal, spring and autumn are the best time to visit. Spring is the time for rhododendrons, while after the monsoon in October and November the clearest skies are discovered.
Nepal is a four-season destination, and the sky is the limit.