Abstract This study investigates the impact of the Madden‐Julian Oscillation (MJO) on North American summer precipitation, focusing on tropical cyclones (TCs). Using observations and state‐of‐the‐art subseasonal‐to‐seasonal (S2S) models, the influence of the MJO on total precipitation (P) and TC‐related precipitation (TCP) is analyzed across MJO phases. Results indicate that TCs significantly contribute to the MJO’s modulation of precipitation, particularly in regions like the Gulf Coast, Florida, and western Mexico. The anomalous probability of extreme precipitation events associated with the MJO is strongly linked to the MJO‐TCP connection, highlighting the importance of capturing these interactions for reliable S2S forecasts of precipitation. We also show that S2S models underestimate TCP’s role in total P anomalies and extreme precipitation probabilities related to the MJO. This underscores the need for improved modeling of the MJO‐TC relationship to increase subseasonal forecast skill of total and extreme precipitation in North America.

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