Winter 2012-2013:

There will be a weak El Nino and a likely negative PDO. In more simple terms, an area of moderately warm waters off the coast off Peru (El Nino) and Cooler waters off the SW coast of Alaska(Negative PDO). So what does this mean for the US? It means that the eastern seaboard will see cooler temperatures so it will be a cooler than normal winter for the eastern third of the country. Also this set of conditions favors a pattern known as the Greenland block. This is when a ridge of high  pressure sits over Greenland and causes the jet stream (which is a “storm highway” and the divide between warm and cold) to dive south into the Eastern US. This ridging will vary from week to week this winter and will not be as strong as 2010-2011. The East will see Above-average precipitation (likely in the form of snow due to below average temperatures. In the Center of the country there will be the other counterpart to the Eastern trough, the high where the jet stream rises warm air and dry air into the nations heartland causing lower than average snow levels and worsening drought. In the Western US it should be a fairly average winter other than the fact that the Pacific storms will be more powerful and more frequent.

Stay tuned!

-Jack