Climate Nepal
A natural staircase that climbs from the tropical zone to the high mountains, Nepal has three climatic zones which, depending on the altitude, extend from east to west in three long parallel ribbons. The diversity of the weather in this country is amazing! Hot and humid, the subtropical region has nothing to do with the Himalayan range, which is very harsh in winter and remains cool in summer. These two opposites, which are one of the attractions of Nepal, are separated by an intermediate temperate climate band, with fairly hot and humid summers and cool winters. But Nepal also lives to the rhythm of the monsoon, which is both a blessing for crop renewal and a hindrance to development. As a result, there are three tourist seasons in Nepal: a high season from October to December, an intermediate one from January to May, and the low season, which corresponds to the monsoon, from June to September.
High season: mild weather but high attendance
October marks the end of the monsoon and, like nature at the beginning of the dry season, the country is getting back to its colours and activities. But it is undeniably the busiest month, all the more so as the tourist influx corresponds to the period of the great holidays of the Nepalese and the festival of Dasaïn. The pure November sky and the still mild temperature over most of the Himalayas favour treks, from the simplest to the most arduous, and thousands of hikers frequent the trails: it is often difficult to find accommodation. Vegetables and fruit abound in the markets, it is good to walk around and visit the sites and towns. Rare thunderstorms of cyclonic origin can briefly fall and snow fall on the passes. The temperature cools down in December, but is very bearable in Kathmandu, where it hardly ever freezes. Fog covers the valley until 10 am and almost every day. At higher altitudes, the crossing of the big passes is now almost impossible. During all this season, in the temperate zone, the good visibility on the Himalayan range allows to undertake hikes in medium altitude, and to enjoy the landscapes and remarkable sites that Nepal offers. A stay in the subtropical zone is also very indicated: the temperature is quite pleasant there, and a lesser humidity makes it possible to visit the natural parks in very good conditions.
The shoulder season offers great opportunities
In the middle of the western winter in January, Nepal often experiences a period of good weather. The sky is clear and the mountains can still be seen from afar. The number of visitors is decreasing, the trekkers who can be found on the trails of the Everest base camp or the Annapurna trails are mostly Australians or Japanese. At high altitude, from March onwards, very rare showers cause snowfall and towards the end of the month, the temperature rises. It is generally in April that the main high altitude passes become accessible again. With the awakening of nature, the first rhododendrons bloom and the season becomes propitious for hiking in the Himalayan foothills up to altitudes close to 4,000 metres. This season also allows travel in areas of average altitude, below 2,500 m. It is especially a good time to visit Pokhara where the traffic is less frequent and the temperature is particularly mild. But you have to accept that the view of the mountains is often blocked by a cloudy cap! At full moon, the biggest winter festivals take place: Shiva Ratri, the night of Shiva, and the Tibetan New Year, an important event in Bodnath and Swayambhunath. At the end of this season, in April, the weather is usually fine everywhere, the heat increases and the Nepalese New Year is celebrated with the new harvests. The ploughing season begins in the drylands and in the highlands. During the following month, the heat rises in the lower valleys and reaches the higher valleys. Yak herders begin their transhumance to the mountain pastures; the biggest Mustang festival, Tiji, takes place in Lho Mantang. In the Kathmandu valley, the end of the month is marked by a veil of mist. Further south, in the tropical zone, temperatures are high, the weather is heavy and the first signs of the monsoon are expected.
The monsoon reaches Nepal from mid-June to mid-September
This climatic phenomenon is so important and brutal that it conditions the life of humans and plants. Its origin goes far beyond the borders of Nepal: in summer, evaporation is extreme on the waters of the Bay of Bengal. At the same time, the rarefied air of the Tibetan plateau becomes lighter under the effect of the sun, causing a formidable phenomenon of aspiration. Moisture-laden clouds rush over the Indian continent and pour their waters over it. Bumping against the great Himalayan barrier, the rains double. Facing south-east-north-west, the monsoon is more violent in the east than in the west and affects the month of July more than August. Water runs off in abundance and invades the country, the view of the mountains is non-existent. Only a few mountainous areas above the clouds can escape the monsoon. The Tibetan plateau, protected by the Himalayan range, receives only a third of this nourishing manna. It is usually in the middle of June that the first monsoon rains reach Nepal. This month of June remains however a very good period to visit the high valleys of the extreme west of Nepal, the Dolpo in particular, which is only slightly affected by the first rains. At the beginning of July, the monsoon usually comes down very violently, causing often devastating floods. Hiking is difficult if not impossible. Around July 15, the Nepalese celebrate the summer solstice, a period of religious impurity that corresponds to the transplanting of rice. Gradually, with the arrival of August, rainfall is reduced to a daily thunderstorm that alternates at the end of the day with beautiful clearings. A great period of festival animates the valley of Kathmandu in the second part of the month. September sees the end of the monsoon, which can curiously end with a resurgence of violent rainfall for a few days. The harvest period and that of the first autumn festivals is launched, a good time to travel to Mustang and Dolpo.
What to put in your suitcase?
Nepal is so varied that your suitcase depends on what you are going to do there! If you are staying in the central zone (Kathmandu, Pokhara...) the mid-season clothes will be adapted: light for the day, with a warm jacket for the evening. If you have to spend time in the southern zone, with its tropical climate, take light, waterproof and natural fiber clothes. Don't forget walking shoes if you have to hike in the forest. If you are going to Nepal on a trek or even in winter, in this case your clothing is very specific: it must be particularly warm and suitable for this type of trip.
