Wettest May weather in decades as El Niño takes a rain check

Australia is currently enduring a deluge, with May rainfall totals in some eastern regions reaching levels not seen in decades. A series of low-pressure systems has saturated the landscape, making this month one of the wettest on record for parts of the country's east.

The focus is currently on northeastern New South Wales and southeastern Queensland, where conditions are ripe for summer-like humidity and instability. This could unleash intense downpours, accompanied by gusty winds and hail. Meanwhile, a separate system is bringing rain and storms to Western Australia, preceding a more significant bout of gales, rain, and storms expected to sweep across the southern states from Sunday to Tuesday.

With the Pacific Ocean on the verge of an El Niño event and parts of eastern Australia having recently re-entered drought conditions, the significant rainfall this May is critical for the nation's agricultural sector. However, the sheer volume of rain has surpassed all expectations, with four distinct low-pressure systems appearing on weather charts within just five days.

Examples of the intense rainfall include 86 millimeters in 48 hours at Dubbo, NSW, marking the wettest May two-day spell on record, and 62mm in 24 hours at Balook, Victoria, the heaviest May rain in at least 27 years. Further north, Brisbane experienced torrential falls of up to 40mm in an hour. The current weather patterns are generating widespread rain, with localized totals potentially exceeding 50mm in just a few hours, prompting flood watches for several NSW catchments. The combination of high moisture, atmospheric instability, and wind shear is creating conditions conducive to severe thunderstorms, capable of producing damaging winds, large hail, and intense downpours.