Abstract:The reliability of FY-4A temperature and humidity profiles are verified by using conventional sounding data and ERA5 data in Guangxi Province during the strong convection processes from February 2019 to February 2020. The results show that: (1) The FY-4A temperature and humidity profiles have lower deviation for the clear sky. Compared with radiosonde data, the root mean squared error (RMSE) of FY-4A temperature with quality control 0 and 1 data ranges from 1.04 ℃ to 4.16 ℃, and the overall RMSE is 2.61 ℃. The inversion accuracy of temperature is better in 850-700 hPa, 600-500 hPa and 250 hPa, all of which have a RMSE less than 2 ℃. The different distribution of temperature profiles between FY-4A and ERA5 is similar to the above. The RMSE ranges from 1.01 ℃ to 4.15 ℃, and the overall RMSE is 2.19 ℃. RMSE is less than 2 ℃ at 925-400 hPa and 250 hPa. (2) The overall RMSE of FY-4A humidity profile is 61.06% compared to radiosonde data under the clear sky, and there is a relatively small error in 900-700 hPa with an averaging RMSE of about 20.51%. The error reaches the maximum near 500 hPa, which may be related to the sudden change of water content in the vertical direction caused by dry air intrusion. In addition, the errors of the lower troposphere are generally smaller than those of the upper troposphere. (3) The reconstructed Tlnp diagram in the strong convection case can restore the temperature and humidity structure characteristics of the upper and lower layers of the atmosphere to a certain extent. However, there is still deviation in the quantitative estimation of stratification stability and unstable energy. The temperature data can better reflect the activity characteristics of cold and warm air after quality control, which provide a prompting effect on the monitoring of strong convective potential. The available high-quality samples are reduced when affected by the cloud, which needs to be corrected by multi-source data in the application.