Precipitation bursts in northern Australia with and without preceding heatwaves

Compound climate extremes have significant societal and ecological impacts, yet their drivers in tropical regions remain poorly understood. For example, although global evidence increasingly highlights interactions between heatwaves and precipitation, the specific mechanisms driving these compound events in Northern Australia remain poorly characterized, particularly the contrasting influence of atmospheric circulation and temperature-driven thermodynamic processes. Motivated by these gaps, this study investigates the interaction between heatwaves and precipitation bursts in Northern Australia during the pre- and post-monsoon seasons. We employ a vertically integrated moisture budget framework to systematically contrast precipitation bursts preceded by heatwaves with those occurring independently. Heatwave-associated bursts exhibit stronger and more prolonged convective activity, resulting in intensified peak precipitation and delayed maxima compared to independently occurring bursts. Vertical moisture advection is the dominant mechanism, accounting for over 70% of the variability in column-integrated moisture flux. A further decomposition reveals that the dynamic component of vertical advection — driven by circulation anomalies — plays a more substantial role than the thermodynamic component in driving these changes. These events coincide with anomalously low mean sea level pressure and enhanced cyclonic circulation, and are observed alongside sustained convective processes. Collectively, our findings highlight the role of atmospheric circulation in shaping these compounded heat and precipitation extremes in tropical Northern Australia.