Seasonal climate summary southern hemisphere (autumn 2015): El Niño arrives

Abstract

Southern hemisphere circulation patterns and associated anomalies for the austral autumn 2015 are reviewed, with an emphasis on Pacific Basin climate indicators and Australian rainfall and temperatures. Autumn 2015 saw the development of El Niño, following a near-miss El Niño in 2014 that never quite met the thresholds needed to declare an event. Australia as a whole received about 20 per cent less rainfall than average for autumn, but tropical cyclone activity contributed to above average rainfall in western parts of Western Australia. Above average rainfall was also seen in some areas in the southern half of the country, while the north was drier than usual. The southwestern half of the continent experienced cooler than normal days, but in the northeastern half of Australia maximum temperatures were above average. A prolonged warm spell affected large parts of Australia during May.