What's Next for the Pacific Northwest?
La Niña Conditions
Weak La Niña conditions are now present in the tropical Pacific Ocean, with the atmosphere reflecting a stronger signal in the outgoing longwave radiation anomalies than what we're seeing in the sea surface temperature (SST) anomalies. Nonetheless, SSTs in the equatorial Pacific Ocean have remained below average over the last four weeks. The "La Niña Advisory" that was issued on November 10 is still in effect. Models are now indicating about a 50% chance that La Niña conditions will persist through the December through February period, but the chances of neutral conditions for that same 3-month period are at about 47% so confidence is low. Neutral conditions are favored over La Niña conditions in late winter and through the spring and summer 2017.
What does this mean for Washington in the coming months?
The CPC January temperature outlook has higher chances of below normal temperatures for eastern WA. Western WA has equal chances of below, equal to, or above normal temperatures for January. There is little indication of how January precipitation will turn out; most of the state is calling for equal chances of below, equal to, or above normal precipitation for the month. Southwestern WA and the eastern most portion of Eastern WA is showing higher chances of above normal precipitation for January.
The CPC outlook for January-February-March (JFM) is reflecting a classic La Niña teleconnection pattern and is calling for increased chances of below normal temperatures for nearly the entire state. A small area in southern WA has equal chances of below, equal to, or above normal temperatures. For precipitation, there are higher chances of above normal precipitation for the entire state for January through March.
Last Updated: 12/16/2016
Climate Prediction Resources
NWS Local 3-Month Temperature Outlook
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