(CNN) -- After the craziness of the winter weather, it's time for some positive predictions, right? Meteorologists are on the lookout for a weather pattern that could mean a milder hurricane season for the East Coast this summer. The National Oceanic and Atmospheric Administration said Thursday that there's about a 50% chance of a weather phenomenon called El Nino developing this summer or fall. That's not a guarantee, but conditions are favorable enough in the next six months to warrant an "El Nino Watch." An El Nino event occurs about once every three to seven years, said Kevin Trenberth, senior scientist at the National Center for Atmospheric Research. It involves the warming of the central and eastern Pacific Ocean, and results in major changes in the jet stream where storms track.
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NOAA: 50% of El Nino this summer or fall
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The pattern would mean warmer atmosphere
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California could get a relief from drought
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Record-breaking El Nino was 1997 to 1998
As the ocean builds up heat in the western @placeholder, some of the heat goes into the atmosphere through evaporation.