 Well, when you're looking at seasonal forecasting across the whole globe, including the United States, the elephants in the room are really El Nino and La Nina. Those are the single biggest things that unfold and vary on cycles of a year or two that affect our climate and weather. So having a handle on them really makes a huge difference. We can think of El Nino as part of an atmospheric triad of sorts. It tends to occur about a third of the time. So maybe one out of every three winters on average in the northern hemisphere will have an El Nino. But we also have neutral conditions, which are neither El Nino or La Nina. And then sometimes you have La Nina. And on average they tend to be sharing the spotlight about equally. El Ninos are a little more frequent, but tend to be shorter. La Ninas will often last a couple of years, and neutral conditions kind of are interspersed between those. When you have each of these going on, there are different effects that tend to happen around the world. So each of them can be good or bad depending on where you live. But the good thing about understanding El Nino and La Nina is that we can predict them to some extent. And that gives people a big heads up on what might happen in their locations. I'm interested in El Nino and La Nina because they are the most beautiful examples we have, I think, of how the large-scale atmosphere and ocean in the tropics can affect each other and lead to big swings in climate worldwide. El Nino southern oscillation events affect wintertime weather over North America, primarily more than the summertime weather. Especially areas on the west coast of the continent, all the way from San Diego to Seattle. El Nino events tend to make Southern California winters wetter. And Seattle often experiences milder conditions, temperatures. Whereas the southeast part of the United States, for example Miami, will experience much colder than normal conditions and in fact can lead to devastating losses of the citrus crops when freezing conditions occur. Earlier this year in the spring, scientists were seeing what they thought were the early indicators of an El Nino event. This fall, however, El Nino seemed to be a bit fickle. But as of November 24th in the past few weeks, we've seen a redevelopment of El Nino conditions and we are now having greater expectation of El Nino conditions this winter. One thing we're really going to want to look for with this El Nino is how it will affect global temperature. It's well established that when you have an El Nino going on, it actually tends to raise the global temperature. And that's because you're taking a storehouse of warm water that is normally sequestered in the western Pacific and fairly deep warm water at that. You're taking that and spreading it out over a larger chunk of the Pacific. That allows the heat to exchange energy with the atmosphere and you literally are heating up the air from below. Some of the highest global temperatures on record have been during El Nino. It looks like 2014 is going to be the warmest year on record and in part because of this even attempt at an El Nino. So if we do get one, it's quite possible that 2015 will be even warmer and set another global record.