As teams are slowly making their way to their base camps, a common question asked every year is “When will they summit?” Of course, we never know for sure but looking at the historical data starting from 1953 to 2017, we can make a very good guess.
The Himalayan Database is a treasure trove of data but it takes some work to find what you want. I spent a bit, actually a lot, time looking at how many people summited each day from both sides, all routes. And there were a few surprises.
The spring season accounts for 96% of all summits on Everest while summer and winter are less than 1%. But the real action takes places on both sides during third week of May, every year. Specifically 80% of all Everest summits occur between the 15th and the 27th of May. Slicing even finer, May 21st is THE day when climbing from Tibet as is May 19th on the Nepal side.
We know that Everest has been summited in all seasons, however you define “seasons” 🙂
Remember that climbing from the Nepal side effectively ends at the end of May when the Icefall Doctors stop maintaining the route through the Khumbu Icefall. As summer approaches, it gets hotter and the monsoon moves in with heavy rain and snow. It becomes too dangerous to be climbing as the Icefall becomes even more unstable. However, since there is no equivalent Khumbu Icefall on the Tibet side, climbers can continue climbing into June or until the monsoon hits that side. As a result we see summits as late as June 14 on the north side.
Summer is miserable with heavy snow up high and sweltering monsoonal rain down low, as a result there are few summer summits, only 9 ever! There are a few days that seem to be significant in the Autumn. Around mid October there is a spike on the Nepal side and slightly earlier on the Tibet side.
For the Visual Readers
This chart shows all the days when all the Everest summits have occured.
So as you can see, summits occur often on Everest but there are a few “auspicious” days. A few more trivia items for you:
- Everest has been summited on 86 different days of the year: 48 from Tibet and 74 from Nepal
- 29 May – first summit of Everest
- 17 February is the earliest, or latest, day that had a summit.
- 27 December is the latest, or earliest, day that had a summit
- There has never been a summit in January, March, July, or November.
- May 11 – 12 people died when a storm took them by surprise
- April 18 – 17 Sherpas were killed when a serac released onto the Icefall.
- April 25 – 19 people died at base camp when an earthquake caused an avalanche
For those of you looking to set a record, here’s your chance – an Everest summit in January or July or…. 🙂
Memories are Everything