@wagirl wrote:
I for one have had enough of ElNino--I live in WA state and from last October thru March, we have had almost 50" of rain!!! The wettest on record!!! Am looking forward to warmer and dryer!!!
@wagirl A Nina winter will be a very wet winter for the Pacific NW, not drier. It could be wetter than last winter.
la Nina winter in pacific NW
http://www.cpc.noaa.gov/products/analysis_monitoring/ensocycle/nawinter.shtml
What is La Nina and how does it affect weather in the Pacific Northwest?
La Nina is the opposite phenomenon of El Nino. During a La Nina episode, the air pressure (on average) becomes slighter lower over the western tropical Pacific Ocean (north of Australia). There is no clear scientific consensus as to why this occurs every three to seven years, but this pressure deviation at the beginning of a La Nina episode causes a chain reaction of other atmospheric & ocean responses:
1) The normal east-to-west winds that blow over the tropical Pacific strengthen.
2) Because of the stronger wind, more “upwelling” in the ocean occurs. (Upwelling is part of an ocean circulation are results in cooler water from below being transported up to the ocean surface.)
3) Because of the increased upwelling, the ocean surface water becomes colder than normal – especially in the central and eastern Pacific areas (off the coast of South America).
4) The colder ocean water results in fewer clouds & thunderstorms over the central Pacific and different pressure deviations that, in turn, alter the pressure and weather patterns all across the planet.
When the tropical Pacific Ocean temperature remains colder than normal (by at least 0.5 degrees Celsius) for at least five months, then the cooling episode is officially classified as a La Nina.
The impacts of a La Nina episode are felt globally. Areas in northern Australia and Southeast Asia become much wetter than normal. And in the United States, the southern tier of states (California & Arizona east through Texas to Florida) typically experience very dry & warm conditions during the winter.
In the Pacific Northwest, La Nina most often results in a wetter than normal winter. Cascade snowfall totals can be significantly above normal during strong La Nina episodes. In the lower elevations, temperatures during La Nina winters are usually near normal or cooler than normal.
More information about El Nino and La Nina:
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