Along sandy coasts, the seaward expansion of dunes starts with the development of embryonic dunes. Vegetation is crucial for their initiation and the subsequent increase in dune height and volume when sediment supply is sufficient. During severe storms, the plants’ tolerance to and recovery from hydrodynamic disturbances, such as exposure to saline water during high water levels and their (partial) removal during storms, is vital to the long-term (months to years) resilience of the dune building process. Accordingly, areas with high embryo dune abundance have been correlated to wider beaches, attributed both to increased wind-driven sediment supply and increased wave attenuation during storms. Recent observations have shown that alongshore variations in subtidal sandbar morphology may also lead to variations in wave attenuation and foredune erosion, following a series of extreme storms. With our research we aim to determine whether subtidal bar characteristics play a role in long-term (months to years) embryo dune development. We first analysed a data set of 112 annual bathymetric profiles (spaced 250 m alongshore) and topographic (airborne Lidar) measurements in addition to observations of embryo dune presence derived from aerial photographs, spanning 50 km along the Dutch coast from 2010 to 2016. Embryo dune area extraction was done by supervised classification of vegetation pixels on the beach. Using a linear regression model, we found that profiles with a more seaward vegetation extent significantly correlated to shallower subtidal bars, in particular during stormy years. Second, to study the timing and alongshore variability of individual erosion events in more detail, we analysed 10 years (2005-2015) of half-hourly images of a 4-km stretch of the same coast, near Egmond aan Zee, in addition to the annual data. These images provide unique observations of the entire bar-beach-dune system, allowing for the concurrent analysis of bar morphology, embryo dune areas and, crucially, embryo dune exposure to saline water and wave action during storm events. At the conference, we will further explain the observed spatial and temporal (storm-driven) variability in embryo dune development.