Close calls, but overall 2015 hurricane season a breeze

When it comes to the actual physical impacts on the Big Island, this year’s hurricane season was a cakewalk compared with 2014.

Last year, Hawaii saw an average number of storms, with five cyclones traveling through the Central Pacific. Unfortunately, one of them — Iselle — ran right into Lower Puna at tropical storm strength, knocking out power for days in some areas, leveling thousands of trees and damaging and even destroying some buildings and property. Millions of dollars were spent clearing roads, restoring power and rebuilding after the storm.

In many ways, East Hawaii still was recuperating when the start to 2015’s hurricane season rolled around May 15, and residents eyed the early forecasts that the 2015 season would be much busier with weary disbelief.

Now, with the season officially coming to a close Monday, we know the forecasts turned out to be right, with a record-breaking 15 storms coming and going through the Central Pacific. The previous record was 11 storms, set in 1994 and 1992, the same year Hurricane Iniki hit Kauai, causing about $1.8 billion in damages.

The 2015 season also saw a record number of times in which multiple cyclones threatened the Central Pacific at once, with three, including Tropical Storms Ela, Halola and Iune overlapping each other at the very start of the season. Later, Hurricanes Kilo, Ignacio and Jimena overlapped each other, marking a particularly harrowing first for Hawaii.

“They were all major hurricanes, Category 3 or higher,” said National Weather Service Meteorologist Chris Brenchley. “It was the first time we’d ever had that. It was unnerving. We were asking ourselves, ‘What are the chances we’re going to get through this without getting hit?’”

But surprisingly, all of the 2015 storms had few impacts throughout the islands. And a review of the combined tracks of the storms shows just how fortunate Hawaii was to escape without a single landfall.

“This year was extremely quiet,” Brenchley said. “Even when you have a season with only one or two storms, you can get one of them tracking across the state and you can have major impacts, even from a very quiet season. This year was the opposite, luckily. We had so many storms that just curved off to the east and moved north and stayed away or moved harmlessly off to the south and toward the West Pacific.”

There were a few peripheral impacts along east-facing shores. Heavy surf flooded some parts of the Big Island, including areas in Kapoho Vacationland, which are typically susceptible to high seas and big swells, he said.

All things considered, however, the busy hurricane season actually might have benefited the Big Island more than it hurt, he said.

“We did have some pretty heavy rain events with moisture that was dragged around the islands,” Brenchley said. “It actually gave us quite a bit of rainfall during what is typically our dry season, and the drought actually diminished as a result of those.”

Despite how things turned out, though, there were some tense moments during the season when things could have gone differently, he said.

“There were several (storms) that through their life cycle, the model data we looked at suggested that at some point they may directly impact the island,” he said.

For instance, he said, when Hurricane Kilo came along in late August, it began to move in a way very similar to that of Iniki, looking like it would move from the south to the north across the islands.

“That gave us some nerves there, for a little while,” Brenchley said.

Luckily this year, the storms approaching from the east all appeared to meet with resistance from a strong jet stream blowing down across the islands to the south. That created a wind shear that helped tear the storms apart as they approached Hawaii, he said.

However, just as Hurricane Iselle showed, it’s dangerous for residents to believe the myth that Hawaii’s unique topography somehow protects the Big Isle.

“A lot of factors came into play that are not related to terrain at all,” he said. “… It’s really up to the timing of where the system is and where we have any sort of wind shears.”

Hawaii County Civil Defense Administrator Darryl Oliveira agreed.

“If you look at a graphic with all the systems represented, what’s amazing is how clear the area over the islands themselves was,” he said. “I think it was very, very fortunate that some of the conditions lined up to protect us.”

He added his office was particularly gun shy this year, following Iselle.

“Throughout the season, with every event we were putting out messages,” he said. “We took every system and storm and tracked it aggressively. I know it was probably pretty trying on the community. … But being out in the community and talking to people, we found our community here has a very sincere appreciation for the different hazards we’re faced with. We learned with Iselle, we’re not invincible. We are vulnerable. It’s a myth the mountains will prevent it from happening.”

The unusual conditions this season, however, made Civil Defense’s job much harder when it came to giving the public timely information, Oliveira said.

“There was definitely concern, especially for those systems building up intensity closer to the island. … The time element from being a depression to developing into a hurricane was much quicker, and gave us less time to put the community on a hurricane watch or warning,” he said.

The storms also appeared to be far more unpredictable than in years past, as can be seen in the graphic accompanying this article. The yellow lines, representing the 2014 storms, show them generally following a straight east to west pattern. The red lines, from 2015’s storms, however, show a lot of back and forth movement, with storms moving to the north or south, and sometimes turning around.

But in the end, “if you look at the modeling done by the National Weather Service, to their credit, they ended up being fairly right on target. It shows they are improving their capability,” Oliveira said.

Even so, “we still want to maintain public caution. There is a cone of uncertainty, a level of deviation. You can’t take those maps and models to heart. They can turn one way or another, and you could have a completely different situation,” he said.

Ultimately, the best takeaway from 2015 was the reaction of the public to the continued warnings being put out by Civil Defense, Oliveira concluded.

“We appreciate how they reacted to this particular season,” he said. “Everybody wasn’t going out and buying provisions in a last-minute rush. We saw steady increases, but people were planning, they were spreading it out.”

Email Colin M. Stewart at cstewart@hawaiitribune-herald.com.

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Tropical systems in the Central Pacific, 2015

• July 8-10, Tropical Storm Ela

• July 10-12, Tropical Storm Halola

• July 10-13, Tropical Storm Iune

• Aug. 1-7, Hurricane Guillermo

• Aug. 8-13, Hurricane Hilda

• Aug. 20-31, Hurricane Kilo

• Aug. 20-26, Hurricane Loke

• Aug. 27-Sept. 4, Hurricane Ignacio

• Sept. 1-9, Hurricane Jimena

• Sept. 18-22, Tropical Storm Malia

• Sept. 24-28, Tropical Storm Niala

• Oct. 3-8, Hurricane Oho

• Oct. 3-4, Tropical Depression Eight-C

• Oct. 11-15, Tropical Storm Nora

• Oct. 20-26, Tropical Storm Olaf

Tropical systems in the Central Pacific, 2014

• July 17-18, Tropical Storm Wali

• July 27, Hurricane Genevieve

• Aug. 5-9, Hurricane Iselle

• Aug. 8-15, Hurricane Julio

• Oct. 15-26, Hurricane Ana

Data courtesy the National Weather Service’s Central Pacific Hurricane Center