During the past couple of months, the El Nino phase in the Equatorial Pacific Ocean has strengthened slightly. Sea-surface temperatures are running 1 to 2 degrees warmer than average across most of the eastern-central Equatorial Pacific Ocean. That is up about 0.5 degrees from early fall. Current climate models indicate that the present El Nino will persist through at least spring. The January-February temperature outlook is based largely on comparing other years in which a similar El Nino was in place, specifically the winters of 1986-1987 and 2006-2007.
Looking at those particular winters and the latest long-range forecast models indicate that slightly warmer than average temperatures are likely during the second half of winter across portions of the northern Rockies, northern-central plains, Midwest, and Great Lakes. Total heating degree-day deficits between 60 and 180 are expected during January and February across these areas. This should lead to slightly lower than average heating costs.
On the flip side, temperatures are predicted to be slightly cooler than average across much of the Southeast, deep South, and Gulf Coast resulting from a more active and unsettled weather pattern that is typical during El Nino winters. Total heating degree-days during January and February are expected to be 60 to 180 greater than normal, which likely will lead to somewhat higher than average heating bills across these parts. The Northeast may see cooler than average temperatures during the beginning of the period, but on a whole should experience mean temperatures closer to normal.