First, I will begin my ENSO update with the latest model forecasts. About half of the Climate Prediction Center models are forecasting further development of El Nino. They are forecasting a moderate El Nino to develop. The other have are predicting just slightly more development of El Nino over the next few months. In fact, a few of the models are not even forecasting much more development of El Nino for the remainder of the year! Here are a few model forecast links:
http://www.emc.ncep.noaa.gov/research/cmb/sst_forecast/images/cmb.SSTfcst_2D.gif
http://www.emc.ncep.noaa.gov/research/cmb/sst_forecast/images/cmb.recordxy.gif
http://www.emc.ncep.noaa.gov/research/cmb/sst_forecast/images/cmb.SSTfcst_nino3.gif
http://www.emc.ncep.noaa.gov/research/cmb/sst_forecast/images/cmb.SSTfcst_nino34.gif
So far, there are no signs of El Nino besides the fact that there are slightly above average sst anomolies in the EPAC. Most are still only in the one to two degress above normal range. In fact, we are still seeing some minor fluctuations in the EPAC and conditions are still basically neutral.
I am predicting a very weak El Nino episode. I also believe that the minor fluctations that we are still seeing, will begin to diminish in one to two months. That is when we will begin to see the true signs of a WEAK El Nino beginning to take shape. However, we may not begin to see a major chane in the weather pattern until 3-5 months. Since I am forecasting only a weak El Nino, we may not even see any major or dramatic changes in the current pattern. In addition, we will still see at least some neutral conditions.
The eastern Pacific should see an above average season sue to the warm sst anomolies as well as the WPAC. Another reason why we could see an above average season in these two regions, is due to the Madden Julian Oscillation.
Typically, during an El Nino phase, we see a lot of shear in the Atlantic Basin. However, we usually do not see westerly winds during El Nino. This year, the QBO winds are forecasted to be westerly. So we have unfavorable shear due to EL Nino but then we have favorable WBO winds blowing from the west. So I am forecasting neutral conditions in the Atlantic (Shear wise)One of the most important areas to look for shear levels is in the eastern Caribbean. This is where the TUTT is located. I believe the TUTT will be slightly stronger this year than last year but still not as strong as it was during the 2000 season. In addition, we still have warmer than average ssts located off the coast of Africa. Sure there has been a recent cool down BUT, we still have to wait for any possible trends. Another are that has caught some attention, is the Gulf of Mexico. The sea surface temperatures in the Gulf were well below average a month ago. But with Summer approaching, those waters are now beginning to warm up. By June, we could see above normal sea surface temperatures all across the GOM.
Another thing that I have noticed so far this offseason, is the low number of troughs that have been exiting the east coast. Typically during El Nino years, we see less of a chance of a tropical system striking the east coast. However, in my opinion there is a better chance of an east coast landfall this year. Take a look at this:
http://www.cpc.ncep.noaa.gov/products/hurricane/hgt_anom_1000_30d.html
On this map, you see low than average pressure just off the east coast but,you can also see abover average pressure readings in the central Atlantic. Remember that the Bermuda high strengthens as time goes by. So by June, we could have high pressure building from the east Atlantic all the way to the western Atlantic with a trough situated OVER the east coast. This would increases the chances of an east coast landfall.
My conclusion is that we will see a very WEAK El Nino this season. The flucuations in the EPAC will not begin to diminish until May or June. It will take at least a little while longer for El Nino to have any impact on the overall pattern since I am forecasting such a weak episode. So far, I believe that El Nino will be too weak to play a major role on the number of Atlantic storms we will see this upcoming season. In addition, there are many other smaller factors that we need to also monitor that are still pointing to an above average season. One for example, is the above average ssts off the COA. I am also forecasting this El Nino episode to be rather short-lived. In fact, after doing some research on past ENSO events, I believe that neutral conditions will return by May of 2003! This would be just in time for the 2003 Atlantic hurricane season. We could see some signs of a La Nina by September of 2003.
The Tropical Weather Watchers 2002 Atlantic hurricane season forecast will be released May 15th, when my new site opens.
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