Since the ascension of K2 in 2001, Jean- Christophe uses a weather router for his expeditions.
Yan Giezendanner, meteorologist at Météo France lives in and produces the “mountain” bulletin for the valley of Chamonix.  With the previsions of my weather router, I can plan and optimize my ascension strategy to the maximum.

All unsuccessful attempts at altitude are obviously the results of the body being considerably weakened.
The big problems in the Himalayas are the very violent winds which blow regularly between 120 and 180 km/h.
The weather windows are short, when the wind drops, generally there is a front arriving which means clouds and snow falls.
I also reinforce my “security» range with this weather routing, so avoid being surprised by a storm which happened in 1996 on Everest and had such dramatic consequences.
At the time, weather routing wasn’t used or very little on expeditions.
Today, I don’t know any base camps in existence not using this system.