Abstract: To meet the demand for high-precision weather forecasting services under complex terrains for the 14th National Winter Games,the Sub-hundred-meter Numerical Forecast System of Inner Mongolia (SNFS) was developed by integrating large eddy simulation technology and high-resolution terrain data,specifically for the outdoor competition areas of the 14th National Winter Games.This paper uses the observational data from the competition area stations as references,and evaluates the wind field forecasting performance of the SNFS system in the three competition areas based on wind speed forecast evaluation indicators and assessment scores.The results indicate that there is a systematic overestimation of wind speed forecast in the Zhalantun and Kharchin competition areas,while an underestimation in the Liangcheng competition area.For stations at lower elevations,the forecast and observed wind speed deviations are mainly positive; with increasing station elevation,the wind speed deviations turn to negative and become more dispersed.The forecast for Zhalantun and Kharchin competition areas tend to overestimate the wind weaker than Grade 6 and underestimated the wind stronger than or equal to Grade 6 in different lead times; while the Liangcheng competition area consistently underestimates the wind,and the Zhalantun competition area shows a significant advantage in forecast score.Further analysis of an individual case of strong wind weather in the Zhalantun competition area shows that,the forecast wind direction is generally consistent with the observed wind direction,and the trend of wind speed change.The SNFS system can characterize the local flow field characteristics and has good forecasting capability for wind fields under complex terrains.

Key words: Mesoscale model, Complex terrain, Wind speed forecast, Assessment and verification