WASHINGTON -- An El Nino, which can alter weather worldwide, has formed but it's so weak and late that it shouldn't be a big deal, U.S. forecasters said.
The National Oceanic and Atmospheric Administration announced Thursday that the climate feature formed in the central Pacific, but forecasters don't expect it to last more than three or four months.
An El Nino is a natural warming of the ocean that once it interacts with the atmosphere often warms up the globe and changes rainfall and temperature patterns, making some places wetter and some places drier.
When there is an El Nino, there are generally fewer and weaker hurricanes in the Atlantic, but this one might not make it to summer and have any effect on the next storm season, said Mike Halpert, deputy director for the NOAA's Climate Prediction Center.
A wintertime El Nino often means more rain for the U.S. South and Southern California, but this is late in the season and it's already rainy there, Halpert said.
The current El Nino is quite different than the last one in 2016, which was one of the strongest meteorologists have seen and helped push Earth to its warmest year on record.
This year's version is "kind of limping along," Halpert said. So he and other scientists said they don't expect many significant effects.
Forecasters had been waiting for it since last June when NOAA issued its first El Nino watch. But while the water was warmer than normal in the Pacific, it wasn't causing the changes in the air that would satisfy the definition for El Nino.
During stronger past El Ninos, the U.S. economy has benefited because of less drought and fewer hurricanes, economic studies show.
Follow Seth Borenstein on Twitter: @borenbears
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