To better understand the local wind systems in the Himalayas, wind and related atmospheric parameters were observed in the Rongbuk Valley on the northern slope of Mt. Everest, during the HEST2006 campaign, from May 29 to June 29, 2006. Data analysis and a simple numerical simulation show that the dominating down‐valley flow in this valley is mainly formed by the thermally driven winds, “valley wind”, “mountain wind” and “glacier wind”. The vertical air motion is composed of a descending flow from the morning to midnight and an ascending flow for the rest of the day, with important modification from the vertical component of the above down‐valley flow and a compensation flow of the “slope wind”. The analysis also shows that the local wind system is well confined in the Rongbuk Valley due to topographic shielding effects.

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To understand the heat exchange processes in the Tibetan mountains, the near surface turbulent heat transfers are analyzed based on the observations in the Rongbuk Valley on the northern slope of Mt. Everest during the HEST2006 campaign from June 1 to 29, 2006. The turbulent heat transfers are directed from the surface to the atmosphere in this valley. The averaged total heat flux is 102.1 W/m2, with a Bowen ratio of 2.17. This heat transfers are closely related to the south Asian summer monsoon (SASM) activities, with a large flux of 129.2 W/m2 during the SASM break period and a small flux of 79.8 W/m2 during the active period. The difference between the heat transfers of the two SASM periods is mainly caused by the enlarged sensible heat transfer in the SASM break period.

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Based on the observational data from the HEST2006 campaign in the Rongbuk Valley on the northern slope of Mt. Everest, in June, 2006, the variation of surface wind in the Rongbuk Valley and possible impact of the South Asian summer monsoon (SASM) on the surface wind are analyzed. During the observation campaign, SASM experienced a break stage and an active stage in middle and late June, 2006, respectively. The surface wind variation measured in the Rongbuk Valley is closely related to the SASM evolution, with a strong down‐valley wind coinciding with the break stage of SASM and a weak down‐valley wind with the active stage. It is suggested that the impact of SASM on the surface wind on the northern slope of Mt. Everest can be attributed to change of radiation conditions.

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