* Little chance of weather problems from El Nino seen into winter
* Weather forecaster says ocean temperatures near average in April
* Confidence in extended forecasts increases after May
NEW YORK, May 9 (Reuters) - The National Oceanic and Atmospheric Administration said on Thursday the latest data confirmed its forecast that El Nino was unlikely to cause extreme weather in the Northern Hemisphere throughout the summer and into winter.
The key U.S. weather forecaster's Climate Prediction Center said in a monthly report most El Nino indices were near zero throughout April and ocean temperatures remained near average.
The phenomenon known as El Nino heats up tropical oceans in East Asia, sending warm air into the United States and South America, often causing flooding and heavy rains.
It can also trigger drought conditions in Southeast Asia and Australia, regions that produce some of the world's major food staples, such as sugar cane and grains.
Current predictions indicate little impact from El Nino is likely into the second half of the Northern Hemisphere summer.
The weather center also said it expected a neutral El Nino outlook for the Northern Hemisphere into winter, but its confidence in the extended forecast was low.
"There is still low confidence in the forecasts for the latter half of the year, partly because of the so-called spring barrier," which historically impedes forecasts between March and May, the center said. However, confidence in the forecasts will rise over the next few months, it said. (Reporting by Carole Vaporean; Editing by Kenneth Barry)