Hurricane Season 2020 Recap
Hurricane season is over, and while it wasn’t as active as in years past, one major storm moved dangerously close to the Hawaiian Islands.
The 2020 hurricane season featured two tropical cyclones in the Central Pacific Hurricane Center (CPHC) area of responsibility, which is below the seasonal average. Hurricane season runs from June 1 to Nov. 30 every year. The Central Pacific basin extends from 140°W to the International Date Line north of the equator. Four to five tropical cyclones occur during an average year.
Tropical Depression Boris was the first tropical cyclone of the season in the Central Pacific, moving into the basin from the east on June 27 and weakening to a remnant low on June 28. Boris was only the second tropical cyclone to occur during June in the Central Pacific since 1950, and the first since Tropical Storm Barbara in 2001.
Hurricane Douglas entered the basin on July 24 as a category 4 major hurricane on the Saffir-Simpson Hurricane Wind Scale. Douglas quickly and steadily tracked to the west-northwest toward Hawai‘i and gradually weakened, eventually passing within 30 miles north of the state on July 26 as a category 1 hurricane.
Douglas weakened to a remnant low on July 29, shortly before crossing the International Date Line into the western Pacific basin. (Note: the dates provided are Universal Coordinated Time [UTC], which is 10 hours ahead of Hawai‘i Standard Time.)
Hurricane Douglas prompted hurricane warnings for Maui County, O‘ahu, and Kaua‘i County; and a tropical storm warning for Hawai‘i County.
Impacts to the State of Hawai‘i: Hurricane Douglas passed just north of the state, keeping the most damaging wind and rain impacts away from land. Swells from Douglas brought high surf across east-facing shores beginning July 25. Heavy rain occurred over portions of the state on July 26, south of Douglas’s track, with no significant property damage or injuries reported.
Additional information about wind gust and rainfall totals from Hurricane Douglas is available here.
Hurricane Season Outlook
NOAA’s 2020 hurricane season outlook issued on May 20, 2020, called for two to six tropical cyclones in the Central Pacific basin, with a 75% chance of near-to-below-normal tropical cyclone activity and a 25% chance of above-normal activity.
The 2020 season started with ENSO-neutral conditions in the equatorial Pacific that were expected to continue through the summer, with a potential transition to La Niña. Equatorial ocean temperatures steadily cooled during the summer, leading the Climate Prediction Center to declare that La Niña conditions were present in August.