Haors located in the north-eastern region of Bangladesh are characterized by large round shaped floodplain depressions and marshy lands. But the Surma-Kushiyara river system known as Haor basin is anticipated to be under additional stress that climate change will certainly bring to its temperature and rainfall pattern. Therefore, daily temperature and precipitation simulations of 17-member ensembles generated by Hadley Centre Coupled Model (HadCM3) of PRECIS (Providing REgional Climates for Impact Studies) which corresponds to the IPCC-SRES A1B emission scenario are examined to project various aspects of future temperature and rainfall extremes, their magnitude and frequencies. Rclimdex software is used to determine 27 standardized set of extreme indices and they were compared over the space and three time slices, viz. short (2020s, ie 2011–2040), medium (2050s, ie 2041–2070) and long (2080s, ie 2071–2098) considering the 1980s (1971-2000) as the baseline period. For the purpose of analysis three transboundary river systems, namely, Meghalaya, Tripura and Barak are also taken into consideration as they will ultimately contribute to the overall assessment of the hydrologic cycle of Haor basin. This study finds highest variability in both rainfall and temperature during the premonsoon season when flash floods normally occurred. Also, the rainy days are projected to be less frequent and more intense where the deeply flooded haors are situated. The Probability Distribution Frequency (PDF) of all indices show more rightward shifting in future indicating increase in amount. But exceptions are found in case of PDFs of Consecutive Dry Days (CDD) and Consecutive Wet Days (CWD). Decrease in CWD is found more pronounced than that of CDD. Projection on continuous decrease in anomaly of CWD and continuous increase in anomaly of Heavy Rainfall Events (rainfall exceeding 99th percentile, R99p) also support the increasing tendency/anomaly of daily intensity index (SDII). In addition, significant increase in both one day maximum rainfall (RX1) and five day maximum rainfall (RX5) during the premonsoon season shows a tendency towards more occurrences of flash floods with higher magnitude. Though the annual total rainfall does not show any difference (not in magnitude) in its spatial distribution, seasonal patterns of both RX1 and RX5 shows possibilities of the shifting of the affected area from the north-eastern to the further north. This scientific understanding is expected to contribute further advancement in Haor Areas Master Plan (2012).