It was this stationarity that led to a progressive cluster of extreme events from tropical heatwaves in mid February to tropical/ subtropical storms in Eastern Australia to the East Antarctic heatwave of mid March. That is, the weather map looked nearly identical every night in the news bulletins, with a deep-layered tropical inland trough over Queensland and a strong subtropical high over Victoria and New Zealand and extending to form a subpolar high over part of the Southern Ocean. During late January and February, the large-scale atmospheric circulation in the Australian and western Pacific Ocean region had been quasi-stationary for weeks from the tropics to Antarctica. The weather was very different to that associated with the landfall or decay of TCs and TLs and involved the formation of a tropical dip that is an inland trough system extending from the tropics to the subtropics. Two different storm events produced extreme flooding events from the 23 rd of February to 9 th of March, 2022. This article investigates the meteorology and related impacts of the storm cluster in 3 phases beginning on the 23 rd of February and finishing on the 2 nd of April. However, the synoptic nature and the cluster of three storms causing extreme rainfall, flooding and complex impacts such as widespread landslides in the SE Queensland, Northern NSW and the Central to Illawarra Coasts is rare and requires analysis to place them in the historical and future climate context. Similarly, the transition from inland troughs to the formation of ECL storms during the autumn – early winter seasons also are typical of Eastern Australian climate. They are also singular events that last 2-3 days but are typically part of a seasonal chain of TCs or TLs that track southwards in the Coral Sea during La Nina summers. Such weather events provide communities and authorities time to prepare based on the probability of landfall location. Forecasting rainfall intensity and spatial coverage during the decay of tropical cyclones and lows is dependent upon the track of the TC or TL, with the greatest uncertainty being the latitude of landfall. There are numerous analogues for these weather events including the 20 events. Moderate to severe late summer flooding in eastern Australia is usually associated with the southward passage of tropical cyclones (TC) and lows (TL) making landfall and/ or transition to an East Coast Low (ECL) between Hervey Bay and Yamba. Here we describe the weather driving these events and place them in some historical context. Flooding in late February, March and early April caused significant damage along large sections of the Australian east coast.
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