The Riverina Bioregion is characterised by hot summers and cool winters (Stern et al. 2000) with the highest levels of rainfall occuring in May and September (Eardley 1999). Summer rainfall tends to occur mainly from localised thunderstorms, with more consistent rainfall occurring in the winter months.
Annual rainfall tends to increase from west to east and from north to south. This is consistent with the northern tip of the region being subject to a warm semi-arid climate and the southeastern edge subject to a subhumid climatic zone (Stern et al. 2000).
see Riverina Climate