Estimation of Convective Atmospheric Instability during Squalls, Tornadoes, and Large Hail Events from Satellite Observations and ERA5 Reanalysis Data

We consider the applicability of satellite data to the estimation of atmospheric instability and precipitable water for the cases of severe convective events occurring over European Russia and the Ural region. The initial sample includes 305 squalls, tornadoes, and large hail events. We assess the instability parameter Lifted Index (LI) and precipitable water (PW) using MODIS Atmospheric Profile Product data and the ERA5 reanalysis data. It is found that the median values of LI and PW retrieved from MODIS and ERA5 data are close, while the extreme values are substantially different. Local areas with very strong instability and high PW are identified from MODIS data, but not detected by the reanalysis data. The MODIS data are found to be significantly limited because of the low frequency of imagery and the lack of information on the instability parameters for cloudy pixels; therefore, the sample size was reduced from 305 to 95 cases.