Weather forecasters are predicting a possible above-average hurricane season this year. Or maybe not.
The Central Pacific Hurricane Center on Wednesday predicted an 80 percent chance of normal or above-normal tropical cyclone action during the Central Pacific hurricane season from June to November.
The 2018 outlook calls for three to six tropical cyclones, with equal 40 percent chances of an above-normal and normal season and a 20 percent chance of a below-normal season.
An average hurricane season has four to five tropical cyclones, which include tropical depressions, named storms and hurricanes. An above-average season has six or more cyclones, forecasters said.
At a news conference at the University of Hawaii at Manoa, National Weather Service officials also predicted a rainy dry season, mainly affecting windward areas across the state as well as the Kona slopes of Hawaii island.
What’s more, leeward areas (other than Kona) are expected to experience “normal dry conditions” from May through September while avoiding widespread severe drought.
The outlook, forecasters said, reflects the El Nino neutral conditions that are forecast by the National Oceanic and Atmospheric Administration’s Climate Prediction Center for most of the hurricane season, with a possible transition to a weak El Nino during the latter part of the season.
El Nino is the global weather pattern triggered by warming water at the Pacific’s equator. In the Central Pacific, El Nino typically means a more active hurricane season as wind shear decreases and water temperatures heat up, allowing hurricanes that develop in the Eastern Pacific to travel farther into our neighborhood.
Forecasters said that if El Nino conditions develop later this year, tropical cyclone activity is likely to be closer to the higher end of the predicted range.
Last year’s hurricane forecast was similar to this year’s, but the Central Pacific only saw two significant storms as El Nino failed to materialize. Those two storms didn’t come anywhere near the islands.
“Thankfully, it was a break after some really busy years,” said Robert Ballard, science and operations officer at the Central Pacific Hurricane Center. “I think everybody was saying, ‘Enough already. Let’s take a break,’ and we got that.”
Meanwhile, Hawaii emergency management officials already are dealing with two disasters: the current Kilauea eruption and the aftermath of April’s storm that dumped nearly 50 inches of rain on the north coast of Kauai and also slammed neighborhoods in East Oahu.
The April 13-16 storm was one of the highlights of the rainiest Hawaii wet season in 14 years but, surprisingly, only the fifth rainiest over the last 30 years, said Kevin Kodama, National Weather Service hydrologist. The 1988-89 season was the wettest, he said.
Overall, the October- through-April rainy season was erratic, Kodama said, with a generally wet October and November, a fairly dry December and January followed by a “very wet” February, March and April.
Most rain gauges over the season recorded rainfall totals 110 percent to 150 percent of average, he said.
It was so wet that the Hawaiian islands became drought-free for the first time since the end of 2015 and remained unaffected by drought for the last three months, the longest drought-free period since 2005, according to the federal Hawaii Drought Monitor.
Because the season was so rainy, Kodama said there could be plenty of fuel for wildfires as the summer turns brush and grasses from green to brown.
As for the hurricane season, forecasters said Hawaii residents should start to get ready now.
“No matter what, everybody needs to be prepared, because, as we say every year, it only takes one. One tropical cyclone that affects you directly can wreck your whole year. You’re going to have a long time to rebuild and you have to be prepared for that,” Ballard said.
“Don’t think it can’t happen here,” he added. “We know the main Hawaiian islands can and will be hit by a hurricane.”
Dennis Hwang, UH Sea Grant faculty member and co-author of the “Homeowners Handbook to Prepare for Natural Hazards,” said the widespread damage to mainland neighborhoods during the devastating 2017 Atlantic hurricane season should act as warning to island residents.
Hwang said homeowners should retrofit and strengthen their aging houses, while residents should maintain a two-week supply of survival provisions and develop an evacuation plan.
Hwang’s book is online at https://bit.ly/2s8VZgI.