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The effects of the diurnal cycle and large‐scale atmospheric disturbances dominate rainfall and cloud variability in the Maritime Continent. This study examines the modulation of the Austral Summer diurnal cycle by the Madden–Julian Oscillation (MJO) using cloud populations through precipitation and deep convective cloud derived from satellite measurements. Using Rainfall Potential Areas from Himawari‐8 Advanced Himawari Imager as a proxy for deep convection, our analysis shows that convective clouds are present ∼55% of the time over land in Sumatra during the afternoon and night. Cloud signatures reveal semi‐diurnal structures of deep convective clouds off the West Coast of Sumatra. In contrast, the East Coast exhibits explicit sea‐ward propagation patterns of deep convective controlled by the coastal effects around the Strait of Malacca and Java Sea, together with the influence of synchronized diurnal forcing between islands. We show that the MJO drives the enhanced convective phases, changing the cloud top type distribution, moisture convergence, and moisture transport over the equatorial Indian Ocean. The cold cloud area also increases during the MJO active phases, which is linked to frequent deep convective cloud development near the mountain ranges of Sumatra and the adjacent ocean. The analyses of cloud variations based on the rainfall potential areas and cloud top type provide evidence of the effects of convective processes on the diurnal cycle of ice and water vapor distribution in the troposphere. This study investigates the different weather patterns affecting rainfall and clouds in the Maritime Continent during the Southern Hemisphere summer. Potential areas of deep convective rainfall are derived from the geostationary satellite Himawari‐8. We found that these clouds experience two life cycles in a single day on the West Coast of Sumatra and the open Indian Ocean, while on the East Coast, their patterns are more complex, potentially due to the influence of the surrounding islands. Additionally, we explore how those convective clouds and their properties change in relation to the Madden‐Julian Oscillation (MJO), an equatorial traveling “pulse” of cloud and rainfall from west to east typically recurring every 30–60 days, during the summer season. Our results suggest that the height of the clouds reaches a maximum, and that ice cloud frequency also increases when the MJO is located over the western region of the Maritime Continent. This study contributes to understanding the effects of the MJO and convective clouds in the daily patterns of ice and water vapor in the atmosphere over Sumatra. Rainfall Potential Areas have shown semi‐diurnal structures of deep convective clouds over the Indian OceanAn explicit sea‐ward propagation pattern of deep convective clouds and complex interactions between island were found in the Java SeaThe cloud top height reaches a maximum in the Madden‐Julian Oscillation convective enhanced phase Rainfall Potential Areas have shown semi‐diurnal structures of deep convective clouds over the Indian Ocean An explicit sea‐ward propagation pattern of deep convective clouds and complex interactions between island were found in the Java Sea The cloud top height reaches a maximum in the Madden‐Julian Oscillation convective enhanced phase