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In this work, we examine the impacts of wintertime western disturbances (WDs) on precipitation over the southeastern Tibetan Plateau (SETP) during 1979–2017. Most WDs initially formed within the central Himalayas and dissipated over southeastern China and its neighboring seas. All extreme precipitation days over the SETP region during this period were linked to WDs, often when a WD center entered the region about 10° west of the SETP. Significant warm temperature anomalies over the SETP region preceding WD arrival favored moisture accumulation there. During the passage of WDs, both strong updrafts along the eastern edge of the WD and rapid decreases in temperature over the SETP (linked to WD‐associated cold anomalies below 300 hPa) favored the occurrence of wintertime precipitation over the SETP region. WD strength and moist static energy variations over the SETP region were key factors affecting the intensity of WD‐induced precipitation, while the size and latitudinal position of the WD played minor roles. The relatively strong WDs that produced extreme precipitation days over the SETP mainly originated above the eastern Mediterranean Sea, northern Arabian Peninsula, and Iranian Plateau. A distinct transition of the circumglobal teleconnection pattern modulated the generation of strong‐intensity WDs within these major genesis regions, as well as their eastward propagation and the generation of extreme precipitation over the SETP region. Key Points: All wintertime extreme precipitation days over the southeastern Tibetan Plateau (SETP) occurred in tandem with western disturbances (WDs)Most WDs with extreme precipitation originated in a band extending from the Eastern Mediterranean to the Iranian PlateauThe circumglobal teleconnection modulated the effects of WDs on precipitation over the SETP [ABSTRACT FROM AUTHOR]

Using ERA5 reanalysis data, this study reveals the relationship between variations of winter surface solar radiation (SSR) over the Southeast Asian low-latitude highlands (SEALLH) and the circumglobal teleconnection (CGT). The results indicate that the winter SSR shows significant interannual variability with a monopole pattern over the SEALLH. The winter CGT significantly modifies the interannual variability of the simultaneous SSR over the SEALLH. When the CGT is in its positive phase, a wave train appears over the central-eastern Mediterranean, Arabian Peninsula, Indian Peninsula, and East Asia with anomalous "northerly, southerly, northerly, southerly" nondivergent meridional wind. The associated southerly wind anomalies around the SEALLH favor greater transport of water vapor from the Bay of Bengal that converges over the SEALLH. The consequent increase of cloud cover in the lower–middle troposphere and aerosol optical depth (AOD) reduce the winter SSR over the SEALLH. When the CGT is in its negative phase, the anomalous northerly wind with anomalous divergence increases the winter SSR over the SEALLH by decreasing both cloud cover in the lower–middle troposphere and the AOD. • The interannual variability of winter SSR shows a monopole pattern over the SEALLH. • CGT impacts the interannual variability of winter SEALLH SSR via exciting a gyre. • Winter SEALLH SSR is regulated by local cloud cover and AOD induced by the gyre. [ABSTRACT FROM AUTHOR]