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La Nina 2012 Will Have a Dry Weather Impact
La Nina is back. Though, meteorology experts indicate it may be weak, California and its Alpen-like ski resorts in and around Lake Tahoe, have already felt its impact.
How La Nina works is that if forms during the winter months with a buildup of warm water in the Pacific ocean, this creates air masses that alter the flow of the Jet Stream, a river-like rush of air that moves the High and Low pressures in weather across the globe. The West coast is impacted first. Usually, much of the winter rain\snow comes from the Gulf of Alaska carried by the Jet Stream, however, La Nina pushes this "river of air" further north so that some of the west coast (California for sure) is bypassed and into the Midwestern states, Pacific Northwest and Great lakes. As the jet Stream is bumped up northwards, the weaker subtropical jet stream takes aim at California, which is dryer at this time of year.
The impact? Already, in Northern California, it has been the driest in 80 years. Farmers are spending a lot money to buy hay and feed. Normally, December is wet, La Nina made it a 'no rain" event. Temperatures have been milder and akin to Springtime. Normally, the ski resorts in the world famous Lake Tahoe region are forced to make snow costing $5000 daily and only on a few key ski runs. Many ski resorts are closing for lack of snow. At Squaw Valley, only 12 inches of it has fallen since Nov. compared to 163 inches last year! At Alpine Meadows, they have a 75% drop in business, normally busy at this time of year. The Tahoe mountain area is as beautiful as the Alps when the snow is there, as of January 2012, it is mostly dry and no snow.
As for forecasts, rainfall from San Francisco south to the border, Arizona, New Mexico, Texas, Oklahoma, Louisiana, through Florida, are expected to have anywhere from 35% to 60% less rain and drought. Northern California, Nevada, Utah all sit on the dividing line. That is, all have a 35% chance that it will be either normal or wetter, or drier.
So far, the word is drier.