There's a strong possibility there could be some drastic changes in island weather this summer.
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The Climate Prediction Center recently issued an El Nino watch. It was the first one since 2012.
From the wind to the waves and the water, when El Nino is active, it can affect every aspect of Hawaii's weather.
El Nino is an unusual warming of the water near the equator.
"Right now we're watching what's called a Kelvin wave, which is a warm pulse of water that's moving eastward across the Pacific (Ocean)," said Kevin Kodama, a hydrologist with the National Weather Service.
The NWS' climate prediction center issued an El Nino watch which means there is a 50 percent chance of seeing El Nino conditions this summer and next winter. If that does happen, it could have a huge impact on island weather.
"(It could mean) three times more hurricanes in the central north Pacific because everything is favorable for hurricane development in this part of the world when El Nino has developed," said Pao Shin Chu, a climatologist with the University of Hawaii.
Both Hurricane Iniki and Iwa formed during El Nino years.
At the other extreme, El Nino can mean very little rainfall during the winter months.
"When an El Nino watch comes out, the (agriculture) community becomes really concerned because we're finally getting some relief this wet season, and now we're bringing the El Nino words again so people are going to be watching very closely," Kodama said.
Abnormally warm ocean waters can also bring large waves on the north shore. The last time the Eddie was a go was 2009, an El Nino year.
It's these potential weather changes that have scientists monitoring ocean water temperatures every week. Just a 1 degree or 2 degree Farenheit increase in average ocean water temperatures can have an exponential impact for Hawaii.
Scientists said they will know in May whether Hawaii will be in for an El Nino year.