Reaching up to 8849m above mean sea level (asl), the upper slopes of Mount Everest provide one of the most climatically extreme environments on the planet. It is also an environment likely to be warming rapidly, due to the tendency for temperature increases to amplify at greater elevations in the troposphere under climate change (Pepin et al., 2015). However, our understanding of high-altitude climates has been severely limited by an understandable lack of basic in situ observations (Matthews, 2020a). The logistical demands associated with climbing to such heights challenges the initial installation of automatic weather stations (AWSs). Those AWSs which do get deployed must then withstand extreme cold and severe winds if they are to remain operational. Mountain regions that are hardest to reach, at those times of year when the weather is most extreme, have therefore been monitored least, meaning winter conditions on the planet’s highest peaks remain largely a mystery. Through necessity, insights have mostly been taken from relatively coarse reanalysis data (Moore and Semple, 2011;