Nepal’s climate varies with its topography. It ranges from tropical to arctic depending upon the altitude. The Terai region, which lies in the tropical southern part of the country, for instance, has a hot, humid climate. The mid-land regions are pleasant almost all year around, although winter morning and nights are cool. The northern mountain region, around an altitude above 3.353 meters has an alpine climate with a considerably lower temperature and thin air in winter can be expected.
Nepal has four climatic seasons:
Spring: March - May,
Summer: June - August,
Autumn: September - November and
Winter: December - February.
Spring is colorful season which is punctuated by the odd shower of life-giving rain but the heat gradually builds until the monsoon relief arrives. During summer the Monsoon; moisture-laden wind, gathers in the Bay of Bengal and sweep up across India to spend its force on the Himalayan mountain chain. Autumn is renowned for clear skies and pleasant temperature. By winter the high hills take dry brown shades and the mountains are occasionally dusted with fresh snow.