During the past month, sea-surface temperatures across the central and eastern equatorial Pacific Ocean have cooled and are now running below average by about one degree. This marks the beginning of the transition from a neutral phase to a La Nina phase that many of the climate models have been predicting. The latest long-range climate models suggest that there is a 70 to 80 percent chance of this La Nina persisting through the upcoming winter season. Also, there are some indications that the NAO (North Atlantic Oscillation) will become negative over the next few weeks, which could play a role in temperatures toward early winter.
As for the November temperature outlook, slightly above normal readings are forecast across parts of the southern Rockies, Desert Southwest, and Southeast. These regions are projected to see a deficit of monthly heating degree days by between 20 and 60 and also slightly lower energy costs with respect to heating. In contrast, parts of the northern Plains and northern Rockies may see temperatures that average slightly below normal in November.
A surplus of heating degree days of between 30 and 60 is forecast across these areas. Much of the Great Lakes, Midwest, Northeast, and West Coast is expected to see temperatures average closer to normal during the month of November.