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Predictions of heavy precipitation alterations in Lithuania are presented. Annual and seasonal precipitation levels and the repeatability of daily and 3-day precipitation cases were analysed. The CCLM (COSMO - Climate Limited-area Model)???? (Fig. 1), developed in Germany, output data of the period 1971-2000 and the prediction for 2001-2100 periods were used. Predictions were based on A1B and B1 emission scenarios and were divided into three periods (2001-2030, 2031-2060, 2061-2100). Daily precipitation data of 18 meteorological stations from Lithuania (Fig. 1) for the period 1971-2000 were also used. The generalized extreme value (GEV) distribution was used to estimate the probability of heavy precipitation alterations. Annual precipitation will increase by about 22% in the 21st century (Fig. 3). Winter time precipitation will rise extremely due to more frequent warm and moist air mass advections; meanwhile, almost no changes will be expected in summer. The changes will be most pronounced in the Žemaiciai Highlands and coastal lowlands (Fig. 2). Also, the number of days with precipitation will rise (by about 5%), especially in spring. Heavy rain repeatability will increase in the Lithuanian territory (Fig. 5). Mostly, one-day heavy precipitation cases will change in the Žemaiciai Highlands and coastal lowlands (>30%) (Fig. 4). The A1B emission scenario predicts greater changes almost in the whole territory, and only in the northern part greater changes are predicted by the B1 emission scenario. In the western part, the changes will be most significant in autumn, while in East Lithuania in winter. Over the first thirty-year period of the 21st century, the same process will affect the repeatability of three-day heavy precipitation cases (Fig. 6). Both scenarios predict great positive changes (up to 50%) in the east as well as in the west. In autumn, the increase of rains will be more significant. A 10-year and a 100-year probability (Table) of daily and three-day heavy precipitation cases will increase in the western part of Lithuania (A1B scenario). Meanwhile, the B1 scenario predicts a decrease of heavy precipitation of 100-year probability in this area. The other parts will experience no changes versus the period 1971-2000. The 10-year probabilities of three-day precipitation maxima vary slightly (Table). A1B predicts a more significant increase in the west and south-west of Lithuania. The 100-year probability of maxima will increase according to A1B, while the B1 scenario shows a slight decrease. [ABSTRACT FROM AUTHOR]