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This study focuses on the primary synoptic‐scale patterns and precursors of extreme and non‐extreme precipitation over the Tibetan Plateau (TP). Atmospheric circulation anomalies and their precursors associated with regional extreme precipitation events (REPE) demonstrate distinct precursor wave train and heightened intensity than regional non‐extreme precipitation events (non‐REPE). Specifically, REPE over the northwestern TP (NWTP) exhibits a geopotential height anomaly induced by a latitudinal propagating Rossby wave train along 40°N. In contrast, over the southeastern TP (SETP), REPE is characterized by a geopotential height anomaly caused by a northwest‐southeastward propagating Rossby wave train. The ascending motion anomalies of REPE over both NWTP and SETP are primarily attributed to the geostrophic zonal temperature advection, which is significantly stronger during REPE compared to non‐REPE. This finding provides valuable insights for forecasting summer extreme precipitation over TP. Plain Language Summary: Tibetan Plateau (TP) is experiencing warming and increased humidity in the context of climate change, leading to a rise in extreme precipitation events. This study focuses on analyzing the circulation patterns and precursors associated with summer extreme precipitation over TP, aiming to identify differences between extreme and non‐extreme precipitation events, as well as explaining the unique characteristics of summer extreme precipitation over TP to answer the question of what distinguishes summer extreme precipitation from non‐extreme precipitation over TP. The findings suggest that summer regional extreme precipitation events (REPE) over the northwest and southeast TP (NWTP and SETP, respectively) display distinct characteristics in terms of atmospheric circulation anomalies and their precursors, which are significantly stronger compared to regional non‐extreme precipitation events (non‐REPE) of varying intensities observed in these two regions. The ascending motion (ω) anomalies responsible for TP's REPE are primarily influenced by the Laplacian of geostrophic zonal temperature advection (term B‐x). Key Points: The extreme precipitation characteristics of the NWTP and SETP, as well as the atmospheric circulation patterns influencing them, exhibit significant disparitiesCirculation anomalies associated with extreme precipitation exhibit a stronger and more distinct precursor wave train, compared to non‐extreme precipitationThe dominant factor driving ascending motion for extreme precipitation over TP is the geostrophic zonal temperature advection [ABSTRACT FROM AUTHOR]

Based on the daily precipitation data of the Huai River basin (HRB) and NCEP/NCAR reanalysis data from 1960 to 2014, the study examines the spatio‐temporal characteristics of summer extreme precipitation (SEP), explores the statistical relationship between the changes of SEP in the HRB and the East Asian summer monsoon (EASM), and further investigates the circulation characteristics which are most conducive to extreme precipitation under different EASM backgrounds. The main results are as follows: (a) summer extreme precipitation indices (SEPI) of PNL90 and PQ90 mainly increased (although not significant) in the HRB from 1960 to 2014, and the weakening of EASM may be the reason for the upwards trend. (b) The characteristics of SEP are quite different between the north and the south of the HRB, and SEPI mainly negatively correlates with East Asian summer monsoon index (EASMI) in the south but positively correlates in the north. (c) Extreme precipitation may occur under both strong and weak summer monsoon backgrounds in the HRB, but the circulation configurations are different. The differences between high and low SEP are mainly associated with the intensity of western Pacific subtropical high (WPSH) for the weak EASM years, while the differences mainly lie in the position of WPSH for the strong EASM years. Extreme precipitation may occur under both strong and weak East Asian summer monsoon (EASM) backgrounds in the Huai River basin, but the circulation configurations are different. Four types of combinations (A, B, C, D) between summer extreme precipitation (SEP) and EASM are classified. The differences between high and low SEP mainly lie in the intensity of western Pacific subtropical high (WPSH) for the weak EASM years, while the differences mainly lie in the position of WPSH for the strong EASM years. [ABSTRACT FROM AUTHOR]

ABSTRACT On the basis of the daily precipitation records of 442 meteorological stations throughout Northeast Asia ( NEA) from 1961 to 2009, this study investigates spatiotemporal changes in summer extreme precipitation ( SEP) and the relationship between SEP and East Asia summer monsoon ( EASM) in NEA. The results show that the spatial patterns of the trends in SEP indices are similar, with obvious clustering, except for the consecutive dry days ( CDD) index. Stations exhibiting increasing trends are mainly located in Eastern China ( EC) and the western part of Western Japan ( WJ). Stations with decreasing trends are mostly distributed in Northern China ( NC) and the southern region of Eastern Japan ( EJ). The spatial patterns of the correlations between the EASM index EASMI and the SEP indices are similar, except for the CDD index. Stations that show decreasing trends mostly exhibit positive correlations between SEP indices and the EASMI, and vice versa. The spatial patterns of trends (increasing trends in EC, decreasing trends in NC and Northeast China) in SEP indices between 1961 and 2009 have a correlation with a weakening EASM. This study demonstrates that the mechanism dominating the mean state change of the EASM also applies to SEP. A strong mid-latitude cyclone could result in a regional SEP (R99p occurred in more than 20 stations over a subregion in 1 day) in EC and Japan in weak EASM years, and could result in a regional SEP in NC in strong EASM years. [ABSTRACT FROM AUTHOR]