The temperatures quoted are for pre-monsoon ascents, April to mid June. Post-monsoon (September to November) temperatures are likely to be a little lower.
For winter ascents (December to February) conditions are very different and these are not covered here.
Please contact us if you have any special needs.
Wind chill rating: Severe
Because of the extreme altitude on Everest, the usual problems of cold are compounded high on the mountain by the fact that you will be moving slowly. Security is paramount, and yet decisions about gear weight are still relevant, not only about what you take, also about what you don't. One of the frequent questions is whether to take a windsuit, which we have addressed in the note on Windchill.