* El Nino unlikely in Northern Hemisphere, but forecast models vary
* CPC has less confidence in forecast beyond spring
NEW YORK, Feb 7 (Reuters) - The National Oceanic and Atmospheric Administration (NOAA), a key U.S. weather forecaster, on Thursday held to its view that the El Ni?o climate phenomenon should pose few weather problems in the Northern Hemisphere through spring.
In its monthly report, the U.S. Climate Prediction Center (CPC), a part of NOAA's National Weather Service, said prediction models overall point to a neutral forecast through spring, though it has less confidence in its outlook for summer.
While maintaining a neutral outlook, the report added that temperature variations in both the ocean and atmosphere increased during January.
Many forecasts showed below-average warmth in the eastern Pacific, but by late January, others pointed to warmer sea waters expanding toward the central Pacific Ocean.
The much-feared El Ni?o weather phenomenon heats up the tropical ocean in East Asia, sending warm air into the United States and South America, and often causing flooding and heavy rains.
It can also trigger drought in Southeast Asia and Australia, which produce some of the world's major food staples, such as sugar cane and grains.
At this point, however, meteorologists think the weather patterns are too weak to look for either El Ni?o or the La Ni?a phenomenon, which arises from cooler sea temperatures.
"Despite these transient features contributing to cool conditions, the collective atmospheric and oceanic system reflects ENSO (El Ni?o)-neutral," CPC said. (Reporting by Carole Vaporean, Editing by G Crosse)