El Niño Splits the Hurricane Season: Busy Pacific, Unusually Quiet Atlantic
El Niño, a climate pattern tied to warm Pacific waters, is linked to a very active hurricane season in the eastern Pacific and an unusually quiet one in the Atlantic. The Pacific has already passed its seasonal average, while the Atlantic has produced just one hurricane.
This year El Niño, a climate pattern linked to unusually warm Pacific Ocean waters, is producing a sharp contrast in tropical storm activity between the Pacific and Atlantic oceans. The eastern Pacific hurricane season has been very busy, while the Atlantic has been unusually quiet.
A busy Pacific season
El Niño tends to strengthen hurricane activity in the eastern Pacific. This season there have already been 22 named storms and 12 hurricanes, 10 of them major. That is above the number typically seen in a whole average season, with two months still to go.
El Niño supplies higher ocean temperatures and weaker winds high in the atmosphere, which makes it easier for storms to gain strength. Hurricane Polo rapidly intensified, producing gusts of 180 mph (285 kmh). It was one of three hurricanes active in the same basin at once, alongside Odalys and Nolo. This has now happened twice in a month: earlier in September, three hurricanes — Lowell, Karina and Marie — were active simultaneously in the central and eastern Pacific. Before this year, the last time three Pacific hurricanes coexisted was 2015.
A quiet Atlantic
The Atlantic is the opposite. El Niño tends to increase wind shear in the north Atlantic, which tears storms apart and limits their formation. There has been only one hurricane, Isaias, which made landfall in the Florida Panhandle and Alabama. It was the latest-forming hurricane on record in the satellite era, which began in the 1960s. The previous record was 11 September, set in 2002 and 2013.
In an average season, there would be 10 named storms, five hurricanes and two major hurricanes by this point. This year there have been only eight tropical storms: Arthur, Bertha, Cristobal, Dolly, Edouard, Fay, Gonzalo and Hanna.
