|MadSci Network: Earth Sciences|
Here's what I can tell you, Cheryl: Well, I'm not a meterologist, but fortunately I was able to locate a Washington Post article on the web that explained the whole thing. What follows is the explanation given in that article: "The warm spell can be credited mostly to a warm air mass from the south that has settled over the eastern United States. That has pushed the polar jet stream -- a high-altitude river of wind that brings winter storms and frosty air into the United States and southeastern Canada -- farther north. "Part of the reason is La Niņa, a global weather pattern that is succeeding the notorious El Niņo. La Niņa, Spanish for 'little girl,' is disrupting normal jet stream paths and is expected to bring cool, wet weather to the Northwest this winter and relatively warm conditions to the Southeast." In short, the jet stream was farther north than usual, which kept the cold arctic air in northern Canada instead of allowing it to come south into the United States - like it is now! Eli Hestermann
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