Lately you might have heard a lot of different people talk about El Niño. Now you might be wondering what exactly this is and how this is going to effect you? Although this question could warrant a very long and complex answer, I will try to give you as brief and simple an explanation as I can.

To start off with, the definition... What is El Niño? El Niño is a global phenomena in which the column of water throughout the equatorial Pacific Ocean warms up. Specifically, the column of water has to be 0.5°C warmer then average value for at least 5 months. This happens in irregular periods from 2-7 years, and can last anywhere from 9 months to 2 years. Now you might be thinking, who cares if the Pacific Ocean is only 0.5°C warmer then average? Well, for a body of water as large as the Pacific Ocean to warm at least 0.5°C warmer then average, that takes a lot of energy, and is a very significant change. Also, if you did not know, the Oceans greatly effect the weather patterns experienced throughout the world. So as the Pacific Ocean warms, the air pressure above the ocean changes, which changes the wind patterns, which changes the movement of air, which changes temperature and rainfall patterns. I reiterate, this is a very basic explanation, as I am trying to keep it as simple and easy to understand as possible. But if you want to go more in depth and get more specifics, the best place for that would be to go to the Climate Prediction Center's El Niño Website at http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtml.

Now that you know what an El Niño is, you are probably wondering why that matters to us here in Central Texas? Well, I mentioned that the ultimate result is that the regular temperature and rainfall patterns change during El Niño years, and that includes the weather that effects us. Lets take a look at a picture that depicts the typical weather patterns for North America during an El Niño winter...

 So there are several changes for Central Texas during an El Niño Winter. We will be under more of a Southwesterly flow aloft due to the Jet Stream sinking more to the south, instead of the Jet Stream diving down on us in a Northwesterly flow. This will affect the types of weather patterns that we see, and then overall, in El Niño winters we are colder than normal and receive more rain than normal.

 Now of course there are stronger El Niño's, and weaker El Niño's, and some other factors (besides being in an El Niño or not) that effect our weather in the Winter. So what does this Winter have in store for us? Well the NOAA just released their 2009 Winter Outlook, and here are their predictions for this winter...

We look to be a little bit cooler then normal, but I think our most noticeable difference will be the amount of rain we receive. Look at the precipitation outlook for this winter...

If this pans out, it looks like the areas that have been hit the hardest by the drought will receive the most amount of rain this winter. Once again, these last two outlooks were part of the NOAA's Winter Outlook and are heavily based upon the fact that we are entering an El Niño Winter, but also take other factors into play. If you want to read more about this report, go to http://www.noaanews.noaa.gov/stories2009/20091015_winteroutlook.html.

To end on an interesting trivia note. The name El Niño is Spanish for "the boy" and refers to the Christ Child. Since El Niño's effects were most noticeable around Christmas time (during winter) when the warmer waters would attract much more fish than usual, thus bringing in a good catch for the local fishermen off the western coast of South America.