Long-lost El Niño arrives, but too late for dry Calif.

Federal scientists Thursday announced an El Niño has formed in the Pacific Ocean.

The climate pattern, defined as warmer-than-average sea-surface temperatures in the central Pacific Ocean, affects weather around the world and often helps spur on needed rain and snow in the West.

But this one will do little for parched California.

"This El Niño is likely too late and too weak to provide much relief for drought-stricken California," said Mike Halpert, deputy director of the Climate Prediction Center, in a statement.

As of today's U.S. Drought Monitor, 98% of California and 99% of Nevada remained in drought, which extends from northern Washington all the way to southern Texas.

The Southeast may see some above-average rainfall, which is typical for an El Niño, Halpert told the Associated Press. El Niños can also knock down the number of Atlantic hurricanes, but increase the ones that form in the Pacific.

There is a 50%-60% chance that El Niño conditions will continue through the Northern Hemisphere's summer of 2015, the prediction center said.

The most recent El Niño, in 2009-10, was a moderate to strong event.