When is the Everest climbing season?

Spring, from April to early June, with almost every summit in the second half of May. For most of the year jet-stream winds of 200 to 300 km/h blast the summit. Just before the monsoon arrives in June they move away for a few days, and that weather window is when nearly everyone goes for the top: to the end of 2024, 81.5% of all summits were made between 15 and 27 May.

How the season runs

Expeditions leave Kathmandu in late March or early April, because they need four to five weeks of acclimatization before a summit attempt. Teams then wait at base camp for a forecast of low wind, and the whole mountain moves up at once, which is why the queues on summit day happen. On the Nepal side most teams aim to summit in May, because warmer June weather makes the Khumbu Icefall more dangerous.

Autumn

A second, smaller window opens after the monsoon, in September and October. Very few expeditions use it: it brings deeper snow, avalanche risk and shorter, colder days, and with no other teams on the mountain you fix all the ropes yourself. The reward is an empty mountain. Winter ascents are rare; the first was in February 1980.

The season and the weather are covered in the guide's Planning your trip, and the summit numbers by month in How many people have climbed Everest?