Temperatures in Alaska, the far West, Southwest and Southern Plains are expected to be above normal for the 2003-04 winter, according to the National Oceanic and Atmospheric Administration (NOAA). However, for the rest of the nation there are equal chances of above-, below- or near-normal temperatures, NOAA said.

“Right now we expect no significant El Nino or La Nina event to influence the upcoming winter weather patterns,” said John Jones, Jr., deputy director of the NOAA’s National Weather Service. “Sea surface temperatures in the key areas of the central Pacific are slightly warmer than normal and they could reach the threshold for a weak El Nino event by the end of November.” However, it is not expected to be significant enough to influence winter temperatures.

“Other factors will play a bigger role,” he said. In cases where a dominant climate feature in the Pacific Ocean is missing, forecasters rely on historical trends of temperature and precipitation averages as well as dynamical and statistical models.

But many other factors and their influence on the winter also are “not yet materially predictable,” he said. Some of those factors include tropical temperatures in the Indian and western Pacific Ocean, atmospheric circulation patterns in the Arctic and North Atlantic, snow cover at high latitudes in late fall, and U.S. soil moisture conditions.

The presence of an El Nino or La Nina make forecasting quite a bit easier in some places and times of year, said Ed O’Lenic, senior meteorologist and lead forecaster at NOAA’s Climate Prediction Center. They “shift the climate for up to a year in such a way that the possible things that can happen are more limited.”

Without them the remaining forecast tools are inadequate this year and currently “imply large uncertainty in the northern and the eastern parts of the United States…

“Like any good New Englander, I think you have to expect just about anything,” said O’Lenic.

“You can describe that anyway you like, and I guess ‘we don’t know’ is one way to describe it,” he said in response to a reporter’s question.

“It’s a bigger challenge when we have a lot of variability. When we say equal chances we are saying that our forecast tools really don’t give us a clear picture one way or the other.”

NOAA’s forecast did project that the multi-year drought in the West (except California) will likely continue with limited improvement and lingering water shortages. The winter outlook will be updated on Nov. 20.

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