There are still no signs of either El Nino or La Nina developing in the Equatorial Pacific Ocean. During the past couple of weeks, much of the Equatorial Pacific has seen sea-surface temperatures near average.
The latest long-range climate models indicate the current neutral ENSO phase likely will persist into spring. Slightly warmer than normal December temperatures are forecast for parts of the Desert Southwest, southern Rockies and southern Plains. Monthly heating degree-day deficits of between 30 and 90 are projected across these regions. Heating costs also likely will be slightly below average.
On the flip side, temperatures are forecast to be slightly colder than normal across parts of the northern Rockies with a surplus of heating degree-days of between 30 and 60. Portions of the Ohio Valley, Midwest and southern Great Lakes also could see slightly colder than normal December temperatures, especially if the NAO (North Atlantic Oscillation) index goes back negative, which appears possible. Monthly heating degree-day totals could be slightly higher than average by between 20 and 40 in these regions.
In general, much of the eastern third of the country will see temperatures close to normal with a few areas a little below normal.