John All fell 70′ down into a crevasse in the Himalayas and survived. He then recorded a video diary of his slow, painful escape:
A couple years ago, Professor All answered the question, why does everyone climb Everest in May?
It comes down to snow, temperature, and wind. “Mount Everest protrudes into the stratosphere, and most of the year the summit is buffeted by winds of over 100 miles per hour that will kill a climber in minutes or even hurtle them into the void,” All told Popular Mechanics. “It is only during the onset or cession of the Asian Monsoon that these winds die down and allow climbers short seven- to 10-day windows to climb the mountain.”
The highest recorded wind speed at the summit was a 175 mph in February 2004. For reference, a Category 5 hurricane has sustained wind speeds of at least 157 mph. Throughout the winter, hurricane-force winds pummel the summit for three days out of four.
The two windows in which those wild winds die down happen in May and September. But snow falls during the September calm, so fresh snow drifts offset the break from the wind. That’s why so many people try the ascent in May, All says.