As many as seven tropical cyclones could hit the Central Pacific this hurricane season.

Forecasters expect the Central Pacific Basin, which includes Hawaii, will experience four to seven tropical cyclones — an uptick from the annual average of four to five for the June-November season, the Central Pacific Hurricane Center announced on Wednesday.

El Nino conditions — when the sea surface temperature is warmer than average — are expected to strengthen heading into the summer and fall, and could cause potentially disastrous storms to develop and retain strength as they travel north toward the isles, officials said.

"(El Nino) does have a tendency to give us more tropical cyclones in our basin and also allow them to hang on a little bit longer toward the end of the season," Tom Evans, acting director of the Central Pacific Hurricane Center, said during the National Weather Service’s annual hurricane outlook news conference at the Hawaii State Civil Defense headquarters in Diamond Head crater.

Hurricane Iniki, the most powerful hurricane to strike Hawaii, barreled through the isles during El Nino conditions in September 1992. Hurricane Iwa also struck during El Nino conditions, near the very end of hurricane season in November 1982.

Forecasters said Wednesday there is an 80 percent chance of normal or above-normal cyclone activity, which includes tropical depressions, tropical storms and hurricanes.

"If we go into a moderate to high El Nino, it’s going to be a better chance of getting tropical cyclones into our area as well as (having them) lingering into the later part of the season," Evans said.

Hurricane preparedness week in Hawaii kicks off Sunday, ahead of the Central Pacific hurricane season’s June 1 start date. The season ends Nov. 30.

"Of course, the reason we’re here is to prepare," Evans said. "That’s the key here, and in preparation we want to look at planning, practice and staying informed. All those three things can keep you safe, keep your loved ones safe and your property safe during significant and severe weather events such as hurricanes."

In a report issued last month, the NWS’ Climate Prediction Center said the chances of an El Nino developing could be up to 50-50 by summer. The center, based in College Park, Md., has since raised that prediction to 65 percent, according to a report published Monday. And the chances of El Nino conditions occurring by late fall/early winter are up to 80 percent.

"We have something that smells very much like a big event," Axel Timmermann, a professor of oceanography with the International Pacific Research Center, said in a phone interview Wednesday.

Timmermann said he fully expects strong El Nino conditions rivaling those of the last big El Nino event of 1997 and 1998 to develop by year’s end.

"The big question remains, again, what will be the peak amplitude?" he said.

Although climate models are still predicting a moderate El Nino event, Timmermann said that could be due to an unexplained "spring predictability barrier" common for this time of year. Evans said during the news conference that forecasters won’t be able to definitively label the ongoing sea surface warming as an official El Nino event until at least July.

The last El Nino event was a weak affair in 2009. After that came two seasons of La Nina conditions, which produced severe cases of drought around the world. The past few years have seen neutral conditions characterized by near-average (zero degrees Celsius) sea temperatures.

Timmermann said if a strong El Nino does develop, La Nina conditions will likely follow.

"All the major El Nino events were followed by La Nina events," he said.

Last year, forecasters expected a below-average hurricane season, but the Central Pacific wound up having an above-average year. There were six cyclones instead of the predicted one to three, partly because upper-level wind patterns early in the season remained more favorable than expected over the eastern parts of the region.

Weak wind shear, for example, helped keep Hurricane Flossie on course to hit Hawaii last year.

Evans said he hopes Flossie, which eventually rolled over the isles as a tropical storm — mostly causing power outages and wind damage to Hawaii and Maui counties — has prompted residents to remain watchful this season, especially as El Nino conditions continue to strengthen.

"That was, hopefully, a wake-up call to say, ‘Hey, this can happen (at) any time — that we could have some sort of hazardous weather event approach and affect the state of Hawaii,’" he said.

The University of Hawaii Sea Grant program was also on hand Wednesday to discuss new public outreach materials that can be found on its website, including best practices for re-roofing prior to having photovoltaic panels installed. Dennis Hwang of the UH Sea Grant program said about 17,000 photovoltaic units were installed in Hawaii last year.

In addition, Evans noted items to pack in an emergency kit: a gallon of water per person and pet for seven days for drinking, hygiene and cooking; food that won’t spoil, such as soups, peanut butter and nuts; important family documents; medications for seven days; and toilet paper. "You’re going to miss this if you don’t have it," he quipped.

CORRECTION: Hurricane Flossie formed in the Central Pacific last year. An earlier version of this story and a story in Thursday’s paper said the storm was on a course for Hawaii in 2007.

POTENT BEGINNINGS

Data from satellites and other ocean sensors indicate that El Nino conditions appear to be developing in the equatorial Pacific Ocean. Conditions in May bear similarities to those of May 1997, a year that brought one of the most potent El Nino events of the 20th century. Hurricane Pauline killed several hundred and caused widespread damage in Mexico. Hurricanes Linda and Guillermo reached Category 5 strength but never made landfall.

IN HAWAII
» Hurricanes Iwa in 1982 and Iniki in 1992 occurred during El Nino years.

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