Portions of the northern Rockies, northern Plains, and upper Midwest are forecast to see temperatures average below normal during the month of December. As a result, a surplus of total monthly heating degree days of between 20 and 40 is projected.
Energy costs with respect to heating are also expected to run slightly higher than average in December. In contrast, parts of the Desert Southwest, southern Rockies, Southeast, and Texas are predicted to see slightly above normal temperatures in December. These regions of the country will likely see heating degree day deficits of between 20 and 60 during the month and at least slightly lower heating costs.
Much of the western United States as well as parts of the Midwest, central Plains, Great Lakes, Mid-Atlantic, and Northeast will see temperatures that on a whole average closer to normal. As for the La Nina watch, sea surface temperatures continue to run near to slightly cooler than average throughout much of the Equatorial Pacific, although not much change has occurred during the past month.
The latest long-range climate models continue to indicate about at 55 to 65 percent chance of at least a weak La Nina developing over the next couple of months. If this does occur, it will likely have some impact of the mid to late winter temperatures across parts of the United States.