KAILUA-KONA — Forecasters are calling for normal to above-normal tropical cyclone activity within the Central Pacific this hurricane season.
Three to six tropical cyclones — a category that includes depressions, storms and hurricanes — are expected to pass through the basin this year, said Robert Ballard, science and operations officer at NOAA’s Central Pacific Hurricane Center in Honolulu. The 2018 Central Pacific hurricane season starts June 1 and runs through Nov. 30.
The basin, which normally sees four to five cyclones develop, spans an area north of the equator from 140 degrees west longitude to the International Date Line. The number of storms has ranged from zero, most recently as 1979, to as many as 11 in 1992 and 1994.
In the center’s outlook, issued Wednesday, forecasters said there is a 40 percent chance of both an above-normal season and normal season, and a 20 percent chance of a below-normal season.
The prediction is based on currently neutral La Nina/El Nino conditions persisting through fall, said Ballard. El Nino correlates with warmer ocean temperatures and reduced vertical shear that can cause increased storm activity while La Nina features cooler waters and historically has produced below normal activity seasons.
However, some models show a 50-50 chance that El Nino conditions will develop as the state heads into winter, post hurricane season, Ballard said. If that happens, the number of storms could be on the higher end of the predicted range.
“No matter what, everybody needs to be prepared because, as we say every year, ‘it only takes one,’ and one tropical cyclone that affects you directly can really wreck your whole your year,” Ballard said. … “And, like we’ve already said, don’t think it can’t happen here because we know the main Hawaiian Islands can and will be hit by hurricanes again.”
Last year, forecasters also called for an near-normal or above-normal season with four to seven tropical cyclones impacting the basin. Just two tropical cyclones passed through the Central Pacific in 2017, down from seven in 2016. The year prior, 2015, was a record breaking season with 16 storms passing through the Central Pacific.
Named Central Pacific tropical cyclones for 2018 will begin with “Walaka,” according to the center.