October-November, the start of the dry season, is in many ways the best time of year: the weather is balmy, the air is clean, visibility is perfect and the country is lush following the monsoon. Its not very hot and not very cold during October -November. In Kathmandu it will be 18 -25 degree. February-April, the tail end of the dry season is the second-best period: visibility is not so good because of dust, but the weather is warm and many of Nepals wonderful wild flowers are in bloom. In December and January the climate and visibility are good but it can be chilly. The rest of the year is fairly unpleasant for travelling: May and early June are generally too hot and dusty for comfort and the monsoon from mid-June to September obscures the mountains in cloud and turns trails and roads to mud.