A Rare and Remarkable Summit: Makalu on an Unusual Timeline

Makalu rarely gives a clean window this late in the season. This one lasted under thirty hours, and it opened where the models had shown nothing but wind at the summit ridge.

The team was in position to use it for one unglamorous reason: the rotation schedule had been held to exactly, including the two days that felt unnecessary at the time. Acclimatisation you have already banked is the only kind available when a window appears with a day's notice.

Reading a window that isn't there yet

Forecast disagreement is information. When two models diverge on summit-ridge wind, the useful question is not which one is right but what each one costs you if you believe it. Staging high and being wrong costs a rest day; staging low and being wrong costs the season.

• Two independent forecasts, checked against what the ridge was actually doing at Camp 3.
• A hard turnaround time agreed before leaving camp, and kept.
• No fixed line above the col until the team was certain of the descent.

We didn't out-guess the forecast. We were just already high enough to act when it changed.

This decision sequence is now taught directly in the cohort's weather and decision-making module — with the actual forecast charts from the day, disagreement included.