1999, Niedźwiedź 2003, Groisman et al. 2005). The first investigations into the spatial distribution and synoptic conditions leading to the formation of extreme precipitation events in Lithuania were carried out by Pečiūrienė (1988) and Tylienė(1988), who analysed heavy rain and strong snowfall events. According to their results, the highest recurrence of extreme precipitation is Forskolin associated with a cold front wave where a secondary depression forms. Bukantis & Valiuškevičienė(2005) found that daily heavy precipitation events had decreased in a large part of Lithuania in 1925–2003; only on the coast were positive tendencies observed. Further

changes in precipitation extremes Ibrutinib ic50 are forecast for the 21st century. The majority of GCM and RCM simulation outputs show an increase in the recurrence of heavy precipitation events during the next one hundred years in Europe (Christensen & Christensen

2004), while negative changes in total precipitation are expected for the southern part of the continent. This means large changes in precipitation frequency rather than in intensity (Räisänen et al. 2004). Also, an increase in heavy precipitation events with a high return period is very likely in Europe (Beniston 2007). However, some investigations show that extreme precipitation events were still underestimated in RCM (Räisänen et al. 2003). Statistical downscaling of GCM (HadCM3 and

ECHAM5) outputs has shown that changes in the annual amount of precipitation in Lithuania will be insignificant. The decrease in summer and autumn precipitation will be compensated by a large increase during winter and spring (Rimkus et al. 2007). A significant increase in the unevenness of precipitation distribution in summer is very likely. More intensive and prolonged droughts will be often followed by very short-lived but extremely intensive rains. The aim of this study was to analyse daily and 3-day heavy precipitation events in Lithuania from 1961 to 2008. The spatial distribution, long-term dynamics and changes in recurrence with a high return period were investigated, and the atmospheric circulation during extreme precipitation events was examined. In addition, possible Erastin changes in the recurrence of daily and 3-day heavy precipitation events in the 21st century were evaluated according to the CCLM (COSMO Climate Limited-area Model) model outputs. Daily data from 17 meteorological stations were used for the analysis of heavy precipitation events in Lithuania (Figure 1). The research covers the period from 1961 to 2008. Stations with almost complete daily precipitation data sets were selected. At some stations, the observations had single gaps (< 1%) which were filled using the ratio method.