Stratospheric Final Warmings fall into two categories with different evolution over the course of the year

Abstract In early spring the stratospheric zonal circulation reverses from westerly to easterly. The transition, called Stratospheric Final Warming (SFW), may be smooth and late, mainly controlled by solar radiative heating of polar region, or abrupt with rapid increase temperature deceleration wind, forced planetary wave activity. Here we present a study, based on 71 years meteorological reanalysis data. Two composites dynamical SFWs have been built. There is very significant difference in evolution during year 60°N wind between two composites. state vortex given month anticorrelated its 2 3 months earlier. Early winter mid-winter late winter/early spring. summer stratosphere keeps memory April–May after SFW until June.