The weak La Nina phase that has been in place across the Equatorial Pacific Ocean for about the past six to eight months is just about completely dissipated and transitioned to a more neutral phase.
The latest long-range forecast climate models suggest that a neutral phase will persist through the first half of this year. However, it should be noted that sea-surface temperatures across the far eastern Pacific off of western South America have warmed by four to five degrees over the last month and are now warmer than average.
This warming will have to be monitored as it could be the beginning signs of an El Nino developing, which could influence temperatures during the late spring and summer. As for the March temperature outlook, slightly above normal temperatures are forecast across parts of the southern Plains, lower Mississippi Valley, and Deep South.
Total monthly heating degree days are projected to be lower by between 20 and 50 and energy costs with respect to heating will also likely be a little lower than average across the regions of the country during the month of March. On the flip side, parts of the northern Plains and upper Midwest may see temperatures average slightly below normal in March, which may result in slightly higher heating costs. Near average temperatures are predicted throughout much of the Great Lakes, Midwest, Northeast, and western United States.