From TWC: La Niña has officially faded away and there is a chance El Niño could develop later this year, according to an update issued Thursday by meteorologists at NOAA's Climate Prediction Center.
Generally weak La Niña conditions have been in place since late fall, meaning cooler-than-average sea surface temperatures stretched across most of the eastern and central equatorial Pacific Ocean.
But an analysis of recent sea surface temperatures indicates water temperatures in that region have retreated to levels that are just slightly below average, and therefore, no longer meeting La Niña criteria.
"Even though it was fairly weak and short-lived ... it did leave impacts," Mike Halpert of NOAA told The Associated Press.
One prominent feature consistent with La Niña this winter has been the above-average temperatures we've seen in the South and mid-Atlantic. The northern Plains saw colder-than-average temperatures in December, which is also consistent with La Niña, but was then near or slightly above average in January.
Perhaps the most pronounced features of La Niña's impact on the atmosphere is the impressively heavy snow and persistent cold in the West, and heavy rainfall near Indonesia.
(MORE: Winter Storms of 2016-17 Season, So Far)
The blue area in the red box indicates cooler than average water temperatures during late-December 2016 in the equatorial Pacific Ocean. That indicates La Niña conditions were present. (NOAA)
NOAA expects neutral conditions to persist through the spring, meaning water temperatures in the equatorial Pacific Ocean will neither be in the La Niña nor El Niño state.
Looking ahead to later this year, it's possible that El Niño could make a reappearance as some climate models are suggesting. NOAA is giving that about a 50 percent chance of happening sometime September-November.
The colored lines on the image below are various model forecasts for water temperature anomalies in the Nino 3.4 region that is used to determine whether La Niña, El Niño or neutral conditions are present in the eastern and central equatorial Pacific Ocean. Neutral conditions means that neither La Niña or El Niño is present.
Through spring, those lines are clustered between the 0.5 and -0.5 degrees Celsius anomalies, meaning neutral conditions are present as NOAA is forecasting. By late summer or fall, the lines for some of the models exceed an anomaly of 0.5 degrees Cesisus, which means El Niño is forecast by those models. Other the other hand, numerous other models are forecasting neutral conditions to persist during that time.
NOAA-CPC did caution, however, that these El Niño/La Niña model forecasts this time of year are very uncertain and that the atmospheric response described above remains very typical of La Niña, despite the recent warming of the sea-surface in the equatorial Pacific.
(MORE: Days Getting Longer, Temperatures Turning Warmer)
Dynamical and statistical model forecasts of three-month mean sea-surface temperature anomalies in the Nino 3.4 region from spring through next fall. (IRI/CPC)
If El Niño did develop later this year it could have impacts on hurricane season, and possibly weather conditions in the United States next fall or winter. But it's far too early to speculate on that, especially since El Niño may never emerge to begin with.
Last winter (2015-16) featured one of the strongest El Niño events on record, with far-reaching impacts around the globe.