Atmospheric circulation during heat waves in Eastern Europe

Abstract

This article aims to describe heat waves in Eastern Europe and to determine the synoptic situations which cause them. In this article, a hot day is defined as the one with a maximum temperature above the 95th percentile of all the values in the analysed period, and a heat wave is considered as a sequence of at least 5 such days. In the analysed period and within the investigated area, from 24 (Kaliningrad) to 55 (Kharkiv) heat waves were observed. The longest heat wave was recorded in Moscow in 2010, lasting as many as 45 days. In the analysed period, an increase in frequency and length of heat waves was observed within the analysed area. The occurrence of heat waves was connected with a high pressure system located over the eastern part of the continent, during which positive anomalies of sea level pressure and the 500 hPa geopotential height as well as positive T850 anomalies were recorded.