The risk of a 'super' El Niño is rising. Here's what it means for North America

The Pacific weather event is under way and likely to intensify in the coming months. This is what it means for hurricane season, food harvests and weather across the US and Canada.

El Niño – the Pacific weather pattern that pushes up global temperatures – has started and is expected to intensify throughout the year, the US National Oceanic and Atmospheric Administration (Noaa) announced on 11 June.

This natural phenomenon occurs when sea surface temperatures in the Pacific Ocean are 0.5C (0.9F) higher than normal for several consecutive months and it typically occurs every two to seven years. The world recently emerged from its cooler counterpart, La Niña.

El Niño and La Niña are naturally occurring phenomena, which result from variations in ocean temperatures and easterly winds in the Pacific Ocean, and disrupt weather patterns worldwide. During El Niño, surface temperatures in the Pacific Ocean are consistently higher than normal. During La Niña, ocean temperatures are lower than normal.

Scientists forecast a 63% chance of sea surface temperatures exceeding 2C (3.6F) later this year. This would make it a "very strong" or "super" El Niño. The last event of this kind occurred in 2015-2016 and resulted in a new global temperature record and a 500-year drought in the Caribbean. (Read more on why El Niño could be the strongest in decades.)

The disruption will be felt most in the tropics, but a strong El Niño will also lead to weather changes across North America, bringing wetter and stormier conditions to the south and drier, hotter temperatures to the north. Here's what scientists say may lie ahead in the coming months.

Quieter Atlantic hurricane season

The earliest impact North America is likely to experience is a quieter-than-normal Atlantic hurricane season, between June and November.

"During an El Niño, the wind environment isn't favourable for hurricane or tropical cyclone development [in the Atlantic]," says William Baule, an atmospheric sciences researcher at Texas A&M University. The increased wind shear makes it harder for thunderstorms to form into hurricanes, he explains. 

Forecasters at Noaa expect a below-normal hurricane season in the Atlantic this year, suggesting at most six hurricanes and 14 storms could emerge this year, with potentially three of these becoming major hurricanes and reaching Category 3 or higher. An average season has 14 storms with seven hurricanes, including three major ones.

Meanwhile, in the Pacific Ocean, hurricane activity is expected to increase as warmer waters provide more energy for storms to form. This is mainly expected to impact western Mexico, says Nat Johnson, a meteorologist in Noaa's El Niño–Southern Oscillation forecast team. 

"Even though Hawaii does not see direct landfalls from........

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