The best months are April to May and September to November. Dolpo sits in the rain shadow of the Himalaya, so the monsoon is drier than in central Nepal, but flights can still be disrupted by cloud.
A rain-shadow lake with three good seasons
Because Phoksundo lies behind the great range, the monsoon is much lighter than in the rest of Nepal. That makes the lake a rare trek that works in summer as well as in spring and autumn. Winter is the only season that is difficult.
Spring, March to May
The valley fills with green after snow, and rhododendrons and other shrubs bloom on the lower sections. April and May are generally comfortable. Snow can linger on the higher sections early in the season. Expect the first clear views of the lake in daylight.
Summer, June to August
Cloud and showers do occur, but they are far milder than in the central hills. The advantage is the green landscape and the almost empty trail. A rain jacket is still a necessity, and landslides on the lower section can slow progress. Flights to Juphal are more likely to be delayed than in other months.
Autumn, September to November
Stable weather, clear light and the best views make this the most popular season. Days are warm and nights fall well below freezing by November. If you want one safe choice, pick October.
Winter, December to February
Snow lies above about 2,500 m, the lodges close, and the route is far harder. Only well-prepared groups with winter experience should attempt it.
What each season feels like on the trail
In spring the lower valley is full of birdsong and the river runs fast with snowmelt, which makes the wooden bridges bounce. In summer the barley fields around Ringmo are green and yaks graze near the lake. In autumn the light turns golden and the leaves of birch and walnut turn yellow. These small seasonal differences are worth keeping in mind when you choose dates.
Photography tips
The turquoise colour is strongest in bright, high sun, between about ten in the morning and two in the afternoon. A polarising filter reduces reflections and deepens the blue. Early morning gives soft light on the Bon monastery and the village.
How to choose
Choose October for clarity, May or September for fewer people, and a summer departure if you want to avoid heavy rain and crowds. Keep a spare day in every season for flights. See the flight guide.
