Friday, September 21, 2012

El Nino Falling Apart; Underwater Cold Pool Growing

AU BOM
Latest analysis of underwater temperature anomalies in the Equatorial Pacific indicates that the El Nino is fading fast underwater.

Only two pools of warmer than normal waters exist across the Equatorial Pacific as of the latest analysis, yet another indication that this El Nino may not survive into the winter. Latest model guidance continues to trend weaker than what was being forecasted earlier, in terms of the El Nino.

Also of major interest is the presence of a very large pool of very cold temperature anomalies just about 200 meters under the waters of the El Nino. These cold anomalies have quickly strengthened in recent weeks, prompting extensive fears of the El Nino being destroyed by this. However, physics states that warm air rises and cold air sinks, and this is the same with water. Thus, the colder waters are encouraged to stay below the El Nino, but are not forced. The next several weeks will be crucial in terms of watching this cold pool do its thing.

I am tentatively keeping my prediction of a weak El Nino for the winter, but as we move through Fall, and the atmosphere continues to respond unfavorably to the El Nino, or if the cold pool grows further, the El Nino is seriously at risk for staying alive through winter.

Andrew

9 comments:

Anonymous said...

if the el nino fades..were looking at a winter like last year???:(

Anonymous said...

It's not going anywhere

Anonymous said...

I agree that if this El Nino was in deed falling apart one of the numerous models would have picked up on it and would be showing that. They are showing the current weaking but also show the up tick in about a mont While I am no fan of models anh. I am assuming that is what Andrew is talking about. While I am not a model worshiper they do add value to a forecast. So for now I will respectfully agree to disagree with Andrew.

Andrew said...

Anonymous #1: More than likely it would be a neutral winter. I put up analogues for a situation similar to what would happen on this link:

http://theweathercentre.blogspot.com/2012/09/analogues-for-neutral-enso-negative-pdo.html

Anonymous #2 and #3: I agree- models are a big part in forecasting these days and must be accounted for in any forecast. However, one must not hang on the models 100%, as even the smaller-scale and shorter-range GFS has been very wrong 2 weeks out. Again, models are almost crucial in the 21st century of forecasting, but what i'm seeing isn't matching up with good prospects for an El Nino.

Anonymous said...

Well then why did everyone miss last winter??? There were at least 2 models that consistently showed the warmer than normal winter from months away and still everyone jumped on the cold snowy winter last year until around Christmas when it became painfully obvious that cold and snow weren't in the cards.

Andrew said...

Anonymous: The La Nina supports cold and wet conditions in the Ohio Valley, Midwest, etc. The atmosphere was fully supportive of this, except for the unusually strong polar vortex that kept the cold air locked up, when it should have been flowing south.

Anonymous said...

I disagree regarding that broad brush description of La Nina. Unless it is a very weak La Nina coming off an el Nino (1995-1996) A la Nina above a weak gives the eastern third of the country a warm rainy look with the strom track running of the Rockies up thorugh the Plains intp the upper midwest. I live in the east and have lived through many La Ninas they are very frustrating to those that like cold and snow.

Louey said...

Hey, Sorry this is in non-related post, but I commented this earlier and got no response (Don't blame you, you seem very busy)but if you have time:
(This was to the first daily forecast)
This looks pretty nice. I was just wondering if you could add more regions or clarify where Louisville, KY would go in this (I've seen some consider it the Mississippi Valley, some Ohio Valley, and some Midwest).

:-)

Andrew said...

Anonymous: A La Nina brings cold to the North and warmth to the South, as well as a wet Midwest and Ohio Valley.

Louey: VERY sorry for not responding earlier! For the discussions, I list only the regions that have some 'interesting' weather. Therefore, the regions change with each discussions. Sorry again!