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This study reveals a close connection between interannual variation of the Somalia Jet (SMJ) intensity in boreal spring and the northwest-southeast movement of the South Asian High (SAH) in the following summer based on multiple datasets and numerical experiments. It is found that the summer SAH tends to shift northwestward (southeastward) when the preceding spring SMJ is stronger (weaker). There are two ways by which the spring SMJ intensity affects the following summer SAH. One is via modulating sea surface temperature (SST) in the tropical Indian Ocean and the other is through modulating anomalous heating associated with the Indian summer monsoon rainfall. On one hand, increase in the spring SMJ intensity enhances southwesterly monsoon winds and upward latent heat flux and leads to SST decrease in the tropical western Indian Ocean. The tropical western Indian Ocean cooling further leads to a decrease (increase) in upper-level geopotential height to the southeastern (northwestern) side of the SAH, inducing a northwestward movement of the SAH. On the other hand, increase in the spring SMJ intensity strengthens the Indian summer monsoon and enhances rainfall and atmospheric heating over the Indian subcontinent. The enhanced Indian subcontinent heating induces strong upper-level positive geopotential height to the northwestern side of the SAH, contributing to a northwestward shift of the summer SAH. Results of this study indicate that variation of the spring SMJ intensity is an effective predictor in the prediction of the northwest-southeast movement of the SAH in the following summer. [ABSTRACT FROM AUTHOR]