The peak hiking seasons in Nepal and Bhutan are February to March and October to November, with clear skies and moderate temperatures. In the northern Indian state of Uttarakhand, March to April and September to October offer the best weather without excessive heat. In most areas, views vanish during the rainy monsoon season (June to September). Trekking in deep winter (December to February) can be a bitterly cold experience, best left to accustomed hikers.