WASHINGTON – The weather-roiling El Nino that emerged across the Pacific in June has continued to build and will likely be one of the strongest in more than 75 years, the US Climate Prediction Centre said.

Sea surface temperatures of 1 deg C or more, the hallmark of the phenomenon, have spread across the central and eastern equatorial Pacific, and there’s an 81 per cent chance it will become a very strong El Nino and rank among the “largest events in the historical record going back to 1950”, the agency said in its monthly forecast.

“Even the strongest El Nino events do not lead to the typical impact everywhere, but stronger events can more significantly tilt the odds in favour of expected outcomes,” the Climate Prediction Centre said. El Nino “will strengthen through the end of the year, with a 97 per cent chance it will last through early spring 2027”.

El Nino is closely watched by traders, markets and governments because it offers seasonal insight into weather extremes that can trigger floods, droughts, cold snaps and alter hurricane and typhoon activity across the Atlantic and Pacific. El Nino strengthens wind shear in the Caribbean, disrupting developing tropical storms and hurricanes during the six-month season that began June 1.

Elsewhere, it typically brings cooler, wetter winters to the southern US while increasing the risk of drought and wildfires in Australia.

AccuWeather reduced its forecast for named storms across the Atlantic to 8 to 14 on July 7, down from 11 to 16 the commercial forecaster predicted in March, according to a statement. The 30-year average across the Atlantic is for 14 storms to be named, which happens when they reach tropical storm strength.

There is only a 3 per cent chance the Pacific will return to normal in early spring and no possibility a La Nina, when the ocean cools, will happen. BLOOMBERG

El Nino likely strongest seen in 75 years, say US forecasters