El Nino Update
Early this summer there was talk of a strong El Nino developing in the sub tropical Pacific. El Nino takes place when above normal water temperatures develop in the subtropical Pacific between the west coast of South America and central and western Pacific Ocean.
The development of an El Nino can alter the jet stream pattern and cause changes in the distribution of precipitation across the United States during the winter and early spring seasons.
The intensity during an El Nino is very important as the intensity will help determine who may be impacted the most.
There was initial excitement that a strong El Nino could mean significant rain for California this winter season. The first forecasts of a possible strong El Nino, however, have not come to fruition. All indications suggest that an El Nino will develop this winter and spring, however, it will fall far short of the expectations that were reported on early this summer.
As you can see in the graphic below as of October 10th, an area of warmer water is developing off the northwest coast of South America stretching westward along and near the equator.
The water temperature pattern displayed is only showing the development of a weak El Nino. Also, notice the area of warmest waters in the north central Pacific and the Gulf of Alaska. This area of warmer water temperatures will help send several shots of cold air into the nation’s mid section this winter, much like it did last winter.
As we look at long range forecast modeling for the Pacific Ocean, by December the area of warmer water near the equator does grow and expand some. If the forecast below comes to fruition, a weak to moderate El Nino will develop. Although, a weak to moderate El Nino will not produce as much rainfall this winter for California as a strong El Nino, there is some hope this winter for west coast rains, however, likely not enough rain will fall to put an end to the drought. However, rainfall this winter should be better than last winter for many west coast locations.