This Winter – El Nino or La Nina?
At this time last year we were faced with some much above normal water temperatures in the subtropical Pacific also known as an El Nino. The strongest El Nino since 1998 developed in mid to late 2015 and continued into the first half of 2016.
Last year’s El Nino resulted in a relatively mild winter in regards to temperatures across the lower 48 states during the winter season. Precipitation was above normal in many areas as well. As we head into the new winter season of 2016/17 we find a much different temperature pattern with sea surface water temperatures as compared to last year.
The very warm waters last year between South America and Australia have cooled significantly. The graphic below highlights sea surface temperature anomalies across the globe. Red/orange areas highlight warmer than normal water with white areas a normal with blue areas highlighting below normal temperatures. Blue represents pockets of colder than normal water temperatures.
Of interest are areas of blue patches along and near the equator between South America and Australia. At this time last year a bright orange area was noted showing the strong El Nino. Another area if interest is the warm pool in the Gulf of Alaska. Warm waters in the Gulf of Alaska have been known to enhance the chances for big shots of cold air over the Midwest and East during the winter season. A year later water temperatures have cooled significantly and instead of an El Nino, we will most likely have a weak La Nina.
Long range modeling is suggesting a weak La Nina this winter season. The chart below shows most modeling indicating near or slightly below normal water temperatures. With the exception of a few models, most other models are predicting a cooler Pacific this winter (at or below the 0.0 line).
A weak La Nina is likely going bring a winter with more cold and perhaps more snow than last winter for many areas, especially from east slope of the Rockies and into the Midwest and East. Beef producers should expect a colder winter than last year, with the exception of far west which may have a warmer than normal winter season.