When to trek in Nepal?

Trekking in Nepal can be undertaken throughout the year. Here are four seasons in Nepal. Each season has its distinct attractions to offer. The seasons are classified as:
Autumn season (September to November): This is the most popular season as the sky remains clear and rain is at a minimum. It provides uninterrupted and crystal clear views of the Himalayas for several hundreds of kilometers. This season offers excellent weather and tantalizing mountain views.
Winter season (December to February): Trekking in Nepal on this season known as coldest months with heavy snowfall in the upper hills, crossing the passes at this time can be impossible. It will be foggy on lower elevation and snowfall at high elevetion generally at and above 3000 m.
Spring season (March to May): is the time you can enjoy the view of the majestic mountains with no clouds and this is also the time to enjoy different flora with blooming rhododendrons of vibrant colors and offers different varieties of wild flowers. Days are apparently hot while walking but you can feel relief at night. Days are longer so you can cover bit more distance as well. It is mildly warm at lower elevations and at higher elevation mountain views are excellent and temperature is quite moderate.
Summer season (Jun to August): Summer months, continues up to mid September making travel wet and warm. These times are blessed for the keen botanist as the higher valleys and meadows blossom with flowers and lush vegetation.

However we believe that “Nepal is for all season”.
Low attitude temperature (1000 m to 3000m)
Day : 25º to 27º Celsius
Night : 0º to 5º Celsius
High attitude temperature (above 3000m)
Day : 15º to 18º Celsius
Night :1º to 15º Celsius