Influence of underlying surface on thunderstorm activity

Inhomogeneity of thunderstorm activity is formed against the background of the same synoptically processes. Even within dozens of miles an average number of thunderstorm days and thunderstorm hours can be changed by 1.5-2 times. The authors focus on the spotty spatial distribution of thunderstorm activity in the regions with fairly smooth relief. Analysis of influence of different factors of atmosphere-lithosphere system on irregularity of a spatial distribution of thunder activity was carried out for two regions with different physical and geographical situation and climate: Siberia and Kazakhstan. For revealing the causes of an irregularity of thunder activity in space the analysis of influence of the following factors upon thunder activity was done by the authors: geographical situation of a region as characteristics of remoteness from poles and oceans, orographical peculiarities in a radius of survey of a meteoobserver, air temperature and resiliency of water steam, temperature and humidity characteristics of an underlying surface, quantities of geographical fields anomalies in a region of observation. Irregularity of temperature and humidity condition of underlying surface and orograpy are the most important factors, influencing thunder activity in both regions.