Today, earthobservatory.nasa.gov issued new evidence (below graphic) of the recently announced onset of El Nino.

For New Zealand this could mean more westerlies and drier weather on the way later in the year.  The thought of El Nino will be worrying for farmers in the east of the country who have battled a number of droughts over the past few years.

earthobservatory.nasa.gov: Places where temperatures were near normal are cream-colored, places where temperatures were warmer than normal are red, and places where temperatures were cooler than normal are blue.

An area of dark red occupies the eastern Pacific off the coast of Peru and Ecuador (north of Peru), indicating temperatures were much warmer than average.

Every 3-8 years, the prevailing easterly winds over the eastern equatorial Pacific weaken or reverse, water temperatures in the central and eastern Pacific climb, and rainfall declines over most tropical land areas.

weather.com: Because of the weakening prevailing easterlies, no upwelling of the ocean waters can occur and the sea surface temps continue to climb as the sun warms the same surface ocean waters day in and day out.

It’s the warming of these eastern Pacific waters off the northwestern coast of South America that make up a large piece in the El Nino puzzle.

Meanwhile, again, it is very important to note that the El Nino pattern still has to run its course. We are at the VERY early stages of El Nino and global weather anomalies directly resulting from this current El Nino will take a good deal of time to reveal themselves This is not an instantaneous cause and effect. It’s a marathon, not a sprint.