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The skill of the global climate models (GCMs) to realistically simulate the3 Monsoon Intraseasonal Oscillations (MISOs) is related to the sensitivity of4 their convective parameterization schemes. Here, we show that by coupling5 a simple multicloud parameterization to a coarse resolution aquaplanet GCM,6 realistic MISOs can be simulated. We conduct three different simulations with7 a fixed non-homogeneous Sea-Surface Temperature (SST) mimicking the In-8 dian Ocean/Western Pacific warm pool centered at the three latitudes 5◦N,9 10◦N and 15◦N, respectively, to replicate the seasonal migration of the Trop-10 ical Convergence Zone (TCZ). This results in the generation of mean circu-11 lation resembling the monsoonal flow pattern in boreal summer. Succession12 of eastward propagating Madden-Julian Oscillation (MJO) disturbances with13 phase speed, amplitude and structure similar to summer MJOs are simulated14 when the WP is at 5◦N. When the WP is located over 10◦N, northward and15 eastward propagating MISOs are simulated. This case captures the merid-16 ional seesaw of convection between continental and oceanic TCZ observed17 during boreal summer over south Asia. Westward propagating Rossby-wave18 like disturbances are simulated when the WP is over 15◦N congruous with19 the synoptic disturbances seen over the monsoon trough. The initiation of20 intraseasonal oscillations in the model can occur internally through organi-21 zation of convective events above the WP associated with internal dynam-22 ics.2