Prediction: Toasty trend for 2/3 of U.S.

A pattern in the Atlantic Ocean greatly influences the severity of winters.
SCRIPPS HOWARD
Government climate forecasters offered a little good news Wednesday amid warnings that home heating bills will soar this winter: Expect higher-than-normal temperatures for the western two-thirds of the continental United States from December through February.
The forecast for the Eastern Seaboard is less toasty, however, with the odds equal for warmer, colder or normal winter thermometer readings.
With no El Nino or La Nina pattern in the Pacific, the outlook for rain or snow across the nation is less certain, with no particular trend for it to be drier or wetter over most of the country.
The exceptions are across the Southern tier of states, where the outlook calls for drier-than-normal conditions in much of New Mexico and Arizona and wetter-than-normal conditions across most of Arkansas, Louisiana, Oklahoma and northeastern Texas.
Although the trend is for higher-than-normal average temperatures from the Mississippi and Tennessee valleys and to the west, forecasters noted that there will still be bouts of winter weather, even extreme winter weather, across much of the country.
The Department of Energy, anticipating a normal winter, warned Tuesday that winter heating bills would be 30 percent to 50 percent higher for most families across the country, with the sharpest increases expected for natural gas. However, supplies disrupted by Hurricanes Katrina and Rita are expected to recover by midwinter.
The dominant winter-weather maker is expected to be a climate feature called the North Atlantic Oscillation, which largely guides the position of the jet stream as it moves across the continent.
When the NAO is in a positive phase, the jet stream tends to shift north and keeps Arctic cold bottled up in Canada; during the negative phase, the jet stream dips south of its usual position and sets up the Ohio Valley, the Mid-Atlantic and the Northeast for deep-freeze conditions, big snowstorms and Nor'easters along the coast.
Researchers expect the pattern to flip back and forth a number of times each winter, but so far have been unable to predict when it will change more than a week or two in advance.
While the National Oceanic and Atmospheric Administration uses a set of computer models to generate seasonal forecasts, meteorologists at the private forecasting firm AccuWeather.com in State College, Pa., came to much the same conclusion about the winter in a long-range forecast based on the factors that have created a "hyper-hurricane" season this year.
The private firm's forecast calls for above-normal snowfall in New England and the mountains of the Pacific Northwest, with the center of the country seeing about half the normal amount of snow. It anticipates that temperatures will be as much as 3.5 degrees lower than normal in the Northeast, and up to 4 degrees higher than normal over much of the West.