The best seasons for trekking in Nepal are spring (March to May) and autumn (September to November). During these times, the weather is generally stable, with clear skies and moderate temperatures, ideal for trekking and viewing the Himalayan peaks. Spring also brings blooming rhododendrons and lush landscapes, while autumn offers crisp air and perfect trekking conditions. Winter (December to February) is colder, especially at higher altitudes, but is still suitable for lower-altitude treks. Monsoon season (June to August) brings heavy rainfall, which makes trails muddy and visibility lower, though rain-shadow areas like Mustang and Dolpo are still good options during this time.