Winter weather hard to predict this year: NOAA

WASHINGTON (Reuters) - Winter will be warmer than normal for much of the central United States, but government forecasters said on Thursday this season's weather for the rest of the country will be particularly hard to predict.

That's because sea surface temperatures in the Pacific Ocean have failed to yield the kind of clues to climate patterns that can make forecasts more reliable, the National Oceanic and Atmospheric Administration said in its forecast, which covers the December through February period.

"There was a lot of agonizing over this particular forecast. This would seem to be the toughest one I can recall having to do," said Michael Halpert, deputy director of NOAA's Climate Prediction Center, in an interview.

"Variability is going to be the highlight for this coming winter," Halpert said.

Neither El Nino nor La Nina weather patterns are present this year in the Pacific Ocean, NOAA said.

La Nina refers to an abnormal cooling of sea surface temperatures in the Pacific Ocean, which tends to bring colder weather to the northern and western United States and drier conditions to the South. El Nino refers to a warming of surface temperatures and creates weather opposite of La Nina.

Instead, winter weather will be heavily influenced by other climate patterns over the Arctic and North Atlantic regions.

For now, the forecast calls for a mild winter, with warmer-than-normal weather from the Rocky Mountains to the Appalachian Mountains through February, NOAA said.

The best chance for above-normal temperatures was expected in Missouri, eastern Kansas, Oklahoma and Arkansas, with a lower probability extending into southern Wisconsin, western Ohio and Texas.

But exactly how the weather plays out remains to be seen.

The agency's winter forecast also predicted an equal chance for temperatures to be normal, above normal or below normal on the East Coast and in the western United States, extending into Montana and northern Minnesota.

The forecast could be good news for the Northeast and the Midwest, which are the largest users of heating oil and natural gas, respectively, in the United States.

"It looks like we're going to see a little bit (of weather) for everyone," Halpert said.

The government said it was difficult to predict moisture across most of the country through February.

Above-normal rain and snow was forecast for Missouri, Kansas, Oklahoma and Arkansas. Below-normal precipitation was seen in a narrow swath of the southern United States, extending from Arizona through Texas and Georgia and into Virginia.

Halpert said the winter forecast was further complicated by signs that La Nina could develop during the winter, although he said government forecasters were skeptical that would occur.

NOAA is the latest weather agency to struggle with predicting how things will unfold this winter. Other weather forecasters also have failed to reach a consensus over what conditions will be like.

In the eastern United States, for example, two weather forecasters, including AccuWeather, have predicted the coldest winter since 2003-04. Meanwhile, competitor WSI Corp has called for mostly mild temperatures in the region.

(Editing by Christian Wiessner)