Saturday, September 15, 2012

Model Data Suggests El Nino Will Not Be Recognized This Winter

Table courtesy of BOM/AU.
Model forecasts can be found here: http://www.bom.gov.au/climate/ahead/ENSO-summary.shtml
New model data is suggesting that the El Nino being so tediously monitored in recent days will not be recognized in time for winter. Before we make any conclusions, let's divide these forecasts into a couple categories to enhance better understanding of the situation.

The first category will consist of the first 3 models- the Australian POAMA, the American CFSv2, and the French ARPEGE model. The crucial thing that must be noted with these models is that they started in early September, giving them an advantage over the other models that were started earlier than this. Also, note that these 3 models have a totally different viewpoint on the next 1-3 months, with all models indicating a neutral 1-3 months in terms of ENSO. More monumental is the 4-6 month forecast that covers the winter months. All 3 models now suggest a NEUTRAL winter is in store. Considering underwater cooling is appearing, at the atmosphere remains very stubborn on accepting this El Nino, I can definitely see this as a possibility.

The second category will hold the American GEOS-5 model, the European System 4 (off the ECMWF), the Japanese JMA/MRI-CGCM, and the United Kingdom's GloSea model. First off, note that all of these models started their forecasts on August 1st, meaning that they are at a disadvantage to the first 3 models. These models may not recognize the possibly-occurring downfall of the El Nino, thus flawing their forecasts. The first 1-3 months of these model's forecasts hold a consistent El Nino, but in the 4-6 month forecast, note that all but 1 of these 4 models are showing an El Nino still sticking around. In comparison to the first 3 models, I find these 4 at a significant disadvantage based mainly off when they started their forecast. While you may not see this as a big deal, a month can make a huge difference, and I feel that that is the situation ongoing here.

These are model forecasts, which I have never been too fond of in comparison to analogs and observed conditions. However, based on these observed conditions, I do not find the first 3 models' forecasts to be totally out of line. They are definitely possibilities come winter.

Andrew

11 comments:

ERN WX said...

Still looks cold, snowy for teh Eastern 2/3 of the country. Notice the trough on the mdls in the long range. I don't think you should modify your forecast till November. A weak Nino or neutral is fine with me, but I still am forecasting a weak Nino. This winter could be the winter.

Anonymous said...

Please help to understand how a neutral SST signal would give you a cold and snowy winter for the eastern half of the U.S. I was always under the impression La Nada's usually look similar to a La Nina. Also The CFS V2 model seems confusing I saw their water temp. forecast for Dec. Jan & Feb. issued on 9/4/12 and it looked as though it was still forecasting an El Nino. Any clarification would be appreciated.

Anonymous said...

i dont understand where u said notice the trough in the mdls..i dont see any models

Andrew said...

ERN WX: Let's hope that the LRC repeats this trough pattern through the winter!

Anonymous: If we get a negative NAO and negative AO, combined with a neutral ENSO, snow and cold can be prevalent in the eastern US. La Nada is basically referred to as a La Nina with the effects not being observed, but the waters still showing a La Nina.

Anonymous: The long range forecasts do show a strong trough in the north central US.

Anonymous said...

ok..i keep getting confused. because ive read that la nina winter's give alot of cold temperatures and snow, last year i believe we had la ninam but we have record warmth and record below snowfall.
this year their predicting a el nino..which i believe means colder temps and more snow for the eastern 2/3 states..i live in kentucky. ive heard that both el nino and la nina give both cold and snow..im confused

ERN WX said...

Anonymous, generally the weaker the Nina/Nino the better for cold and snow. Neutral winters after double mdt+ Ninas have a record of being cold and slgtly dry for the eastern half. If it is neutral the NAO will have full control. The GFS and Euro show a trough pattern dominating the Eastern 2/3ds. Weak Nino.

Anonymous said...

so were in for a cold and snowy winter?

ERN WX said...

As of now it looks like we will be in for a cold snowy winter, but since we are still a ways off things may change. Mid-November I think things will be clear.

Anonymous said...

1 more question then ill leave u alone...does kentucky consist of the eastern 2/3rd states?.cuz i live on the ky/tenn border.near nashville

WinterStorm said...

Anonymous,yes.

ERN WX said...

Folks, I see promising signs in the long term.