The diurnal cycle of rainfall over New Guinea in convection-permitting WRF simulations

摘要: Abstract. In this study, we examine the diurnal cycle of rainfall over New Guinea using a series convection-permitting numerical simulations with Weather Research and Forecasting (WRF) model. We focus our on a period suppressed regional-scale conditions (February 2010) during which local forcings are maximised. Additionally, study occurrence dynamics offshore-propagating convective systems that contribute to observed early-morning maximum north-east Guinea. general, modelled precipitation shows good agreement satellite-observed rainfall, albeit some timing intensity differences. The also reproduce variability overnight convection propagate offshore as organised squall lines these is largely controlled by background conditions. Days have more middle tropospheric moisture, larger available potential energy, greater low-level moisture convergence. Convection has similar characteristics terrain days without propagation. manifests via a multi-stage evolutionary process. First, scattered land, remnant daytime maximum, moves towards coast becomes reorganised near region coastal convergence associated land breeze. then in form a squall line at  ∼ 5 m s−1. addition, cool anomalies gravity waves generated precipitating a dry hydrostatic wave speed (of  ∼ 15 m s−1) act destabilise coastal/offshore environment prior arrival line. Although does not appear initiate or control its propagation, it should longevity maintenance. results highlight importance effects along contributing Maritime Continent, especially maxima adjacent quasi-linear coastlines.