A calmer than average hurricane season will end in less than a week after only two tropical cyclones developed in the Central Pacific.
The 2020 hurricane season, which runs from June 1-Nov. 30, was significantly less severe in the Pacific Ocean than in the Atlantic, where 30 named storms have led to that ocean’s most active hurricane season on record.
National Weather Service meteorologist John Bravender said strong seasons in one ocean tend to correlate with weak seasons in the other.
“We look for La Nina conditions, which means stronger trades and more wind shear, but fewer cyclones, in the Pacific,” Bravender said. “During La Nina years, you see more storms during the Atlantic, but not a lot in the Pacific. And vice versa during El Nino, the warmer period, you get more storms in the Pacific, but fewer in the Atlantic.”
The two Central Pacific cyclones generated this year were Tropical Depression Boris and Hurricane Douglas, which were active in late June and July, respectively.
“There’s a strong dichotomy between those two storms, in terms of impact,” Bravender noted. “Boris was weak and didn’t get close to anything, but Douglas headed straight for us and only pulled away at the last minute.”
Douglas was a Category 3 hurricane generating winds of up to 115 mph before it veered northward, circumventing most of the Big Island. Despite tropical storm warnings being issued, the island avoided any significant impacts.
On the other side of the country, a barrage of storms from the Atlantic battered the southeastern United States, with Louisiana and Florida in particular sustaining substantial damage. In August, Hurricane Laura killed 42 people in the U.S. and 35 in the Caribbean, causing more than $14 billion in damage, only for Hurricane Delta to tear across the same path weeks later.
Hawaii’s weak hurricane season also spared the state further complications during the COVID-19 crisis. The intense Atlantic storm season put increasing pressure on states’ already struggling health systems in the midst of the pandemic.
Bravender said the La Nina conditions are expected to last through the winter, but it is too early to predict how the 2021 season will play out. While El Nino and La Nina are cyclical, they are not always regular and, in some cases, have lasted for more than a year.
The last major El Nino period took place throughout 2015, when the Central Pacific had a record 16 tropical cyclones.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.
