<p>It has been demonstrated that rainfall temporal patterns play a critical role in influencing various hydromechanical effects during the triggering process of geo-hazards such as landslides and debris flows. However, the roles of rainfall temporal patterns in the triggering of debris flows have received less attention. In this study, we utilized valuable observed hydrological data, primarily consisting of water discharge measurements collected over two summer months in a small catchment in Zhejiang Province, China. Using a combination of hydrological and hydrodynamic models, we investigated the influence of temporal rainfall intensity distributions on the triggering of debris flows. Our results indicate that rainfall patterns with a delayed peak of intensity, despite having the same duration and total amount as those with an early peak, are more likely to trigger debris flow activity. Specifically, the large values of peak rainfall intensities in such delayed patterns will increase surface flow and subsequently more easily triggered runoff-generated debris flows. We also assess the influence of sediment on the generation of runoff-generated debris flows. The preliminary finding indicates that the magnitude of debris flows is highly sensitive to changes in grain size, surpassing the sensitivity observed in response to rainfall patterns. With the advancements in high-resolution precipitation predictions, our research findings can improve the early warning systems for debris flows. Additionally, our study can aid in identifying the hydrological scenarios that trigger and intensify debris flow activity.&#xa0;</p>