The operational LIght Detection And Ranging (LIDAR) data from the Hong Kong International Airport (HKIA) is assimilated in a six nest, high resolution Weather Research and Forecasting (WRF) model. The existing radar data assimilation schemes in the WRF Data Assimilation (WRF-DA) package have been adapted to accommodate the high temporal frequency and spatial resolution of the LIDAR observations. The weather data is then used to produce Lagrangian coherent structures (LCS) to detect atmospheric hazards for flights. The coherent structures obtained from the various data sets are contrasted against flight data measured onboard aircrafts. It is found that both WRF and WRF-DA produce coherent structures more distinguishable than those obtained from two-dimensional retrieval, which may improve the detection of true windshear hazards.