Baihetan Hydroelectric Power Station is located in the canyon area of the lower reaches of the Jinsha River, with frequent northerly windy weather in the dry season. Objectively identifying the circulation system that affects the strong winds of the hydroelectric power station is beneficial for revealing the formation mechanism of strong winds in special areas. Based on 139 cases of northerly windy weather in the dry season in the canyon area from November 2018 to November 2020 to April of the following year,, this paper analyzes the circulation situation of windy weather, and establishes objective identification conditions with reference to the Lamb-Jenkinson (L-J) method,tests and modifies the identification conditions. The following conclusions are obtained:(1) Fifteen typical northerly winds in hydropower stations are selected, and through the analysis of the characteristics of circulation situation, the upper-air circulation affecting the gale is summarized as: southern branch trough, plateau trough and northern transverse trough. In 15 cases, the first two types appeared 6 times each and the transverse groove type appeared 3 times. (2) Based on the analysis of circulation characteristic parameters by L-J method, the key areas and preliminary identification conditions of gale circulation in dry season are determined. The identification conditions of the south branch trough and plateau trough are that the zonal component u of the geostrophic wind in the key area is greater than 10 dagpm·10olongitude-1, and the difference with the meridional component v is greater than dagpm·10olongitude-1, while The?vorticity of the geostrophic wind. is greater than 0 dagpm·10olongitude-1; The identification condition of transverse groove type is that the critical area u is less than 20 dagpm·10olongitude-1,and it is required to be greater than u. (3)In addition, 14 cases of gales in the dry season of 2021 were selected to test the above circulation identification conditions, and it was found that 11 of them accurately identified the circulation type. According to the reason that the circulation type is not recognized, the thresholds of you and the difference between you and v are corrected, and the results show that the corrected discrimination conditions are accurate and feasible. Finally, the objective identification method of circulation situation can provide a reference for gale warning.