Upper Mustang is a remote arid area of trans-Himalayan mountains. Bordering Tibet, this region has a distinct Tibetan feel – both in its people and culture and in the landscape. High rocky cliffs of unusual formation and colour, caves, rock paintings, monasteries, and, of course, high snowy mountains, are a feature of this region.
Being in the rain shadow, there is no monsoon in this dry region, making it a perfect area to explore during the summer (monsoon in Nepal) months. Winters are harsh, with most of the local population migrating to Pokhara or Kathmandu, so that is not a good time to trek.
Spring Time – April and May
This is a great time to visit Upper Mustang, particularly if trekking in from Lower Mustang as the weather will be warmer and the rivers full of snowmelt in the lower regions.
This time of year is probably best if you are planning to cross high passes or go climbing in Upper Mustang. The middle of May is also the time of the Tiji Festival at Lo-Manthang. This festival lasts for 3 days and is definitely a reason to come in May. See here for further details of Tiji. Temperatures at this time of year are generally between 16 and 22 degrees Celsius.
Level of Difficulty: This is a very good time to trek, but remember Upper Mustang is considered a ‘demanding’ trek, and a good level of fitness is required, with the arid air making the average (for Nepal!) altitude seem higher.
Monsoon – June to September
There is no monsoon in Upper Mustang, which makes it a very good trekking area for those who have to take their annual leave during the summer months. Further down the mountain in Lower Mustang, the trails will be wet and possibly slippery and flights from Pokhara to Jomson may be delayed due to the weather.
But once you reach Upper Mustang it’s a whole different world. The August full moon day is also the date marked for the horse festival, or Yartung Mela as it’s known locally. This 3 or 4 days event starts in Lo-Manthang and travels downwards, with horse races, archery, dancing, and festivities all the way! Temperatures vary from lows of 16 degrees to highs of mid-20s Celsius.
Level of Difficulty: Again this is a good time for trekking in Upper Mustang but do remember that the dry air makes the altitude seem higher than it is, and good fitness is a must. If trekking in from the lower altitudes which are in monsoon mode, you will need gear for wet days.
3. Autumn – October, and November
As across the whole of Nepal, the autumn is the time with the bluest skies and clearest mountain views. Afternoons can be windy though so be prepared! In general, temperatures range from 12 to 20 degrees Celsius.
This is really the end of the trekking season in Upper Mustang as lodges close and villagers migrate to Pokhara and Kathmandu to wait out the harsh winters. Trails disappear under snow and heavy-duty winter gear is required after November.
Level of Difficulty: Other than the same advice of remembering that Upper Mustang is considered a ‘demanding’ trek so a good level of fitness is required, this is a good time to trek and no special gear is required. If you are trekking towards the end of the season, heading into winter, you should be prepared for snow and very low (minus Celsius) temperatures.