The monsoon rains bring landslides and clouds obscure mountain views, though hefty hotel discounts are common. Rain and leeches deter most trekkers, but this is a popular time to travel overland to Tibet.
The second-best time to visit brings warm weather and spectacular springtime rhododendron blooms.
Clear skies and warm days make autumn the peak season. Thousands of people hit the trails in the Everest and Annapurna regions and accommodation in Kathmandu gets booked up as prices peak.