ИСТИНА

The typization of weather conditions and synoptic processes, which led to the formation of the abnormal hot weather in Moscow, was prepared using everyday data archives of GIS Meteo and NCEP/NCAR reanalysis. Conditions of the long-term anticyclone stabilization were considered in detail and the reasons for its regenerations were identified. To obtain blocking anticyclones quantitative characteristics the methodology was proposed to assess the contribution of the planetary vortex advection, advection of vorticity, divergence, vorticity fluxes generated by low - and high-frequency fluctuations and the interaction between them in variations of vorticity. It is shown that the greatest contribution comes from the advection of planetary vorticity, divergence and vorticity flux generated by low-frequency fluctuations. Moreover, the maximum change of the quantitative characteristics in the center of anticyclones begins 6-7 days prior to their gain.