When scientists make their "call" for an El Nino event......the oceans have already warmed in the central equatorial Pacific for MANY MONTHS a considerable amount.
In some ways....that isn't the most "enlightening" of information. Somewhat like calling "the bottom" of the stock market 5 months AFTER it was already rising.
I believe we are LIKELY near a turning point in the sea surface temperatures of the central EQUATORIAL Pacific (if you were to draw a vertical line that starts at the center of the coast of Alaska and head south...........and intersects a horizontal line that you draw from the center of coast of Ecuador towards the WEST.......where those two lines intersect is the area I am talking about).
The ocean waters have been "neutral to cool" in that area for the last several months......and indeed, the area just west of Ecuador has had a very cool anomaly over the past couple of months. All the while.....many other parts of the Pacific have been very warm.
Over the last two weeks.....the "cool anomaly" off the coast of Ecuador has been moderating.....and a few small areas of the central Pacific (due south of Alaska and due west of Ecuador) have been warming (still SMALL areas right now......but everything starts small at the beginning).
I know that NOAA is calling for a likely "neutral" position on El Nino through the end of this year, and they have certain "requirements" (ie monthly average for 5 straight months must exceed a certain amount over the average...etc). But what I am trying to say....is that we are likely NOW at the turning point, where over the next SEVERAL MONTHS....the central Pacific will be heating up......and perhaps towards the fall of this year....that NOAA will be looking towards forecasting an El Nino that will start by the 2nd quarter of 2014 (April or May of 2014).
So when I say "Pre El Nino".....I am talking about the "process" of the beginning of warming waters that MAY likely lead towards an "El Nino event" 8 months or so in the future.
The SECOND MAP from the top of the following link shows the area I am referring to:http://climatechangegraphs.blogspot.com/2013/02/sea-surface-temperature-anomaly-weekly.html