What's Next for the Pacific Northwest?
Neutral El Niño-Southern Oscillation (ENSO) Conditions
Neutral ENSO conditions are still present in the tropical Pacific Ocean, though there has been some warming of sea surface temperatures (SSTs) over the last few weeks. SSTs throughout most of the equatorial Pacific Ocean have been slightly above normal over the last four weeks, but do not exceed 1 degree Celsius above normal at the time of this writing. Neutral conditions are favored through the summer and fall (50-55%), though models indicate that the chances of El Niño development are elevated for the fall (~35%) compared to climatology. Still, neutral conditions persisting is more likely.
What does this mean for Washington in the coming months?
The Climate Prediction Center (CPC) July temperature outlook has increased chances of above normal temperatures for a majority of the state. The highest probability of warmer than normal temperatures is in eastern WA while the Olympic Peninsula has equal chances of below, near-normal, or above normal temperatures for July. The July precipitation outlook shows higher chances of below normal precipitation for most of the state. An exception is south central and southeastern WA, where there are equal chances of below, near-normal, or above normal precipitation for July.
The CPC outlook for late summer (July-August-September; JAS) is calling for increased chances of above normal temperatures for the entire state. The probability of warmer than normal temperatures is slightly higher for locations west of the Cascade Mountains. For precipitation, there are equal chances of below, equal to, or above normal July through September precipitation statewide.
Remember that these outlook percentages are based on a tercile system, and therefore the chances of below, equal to, or above normal temperatures or precipitation are split into equal probabilities of 33%. When there is a greater than a 33% chance of an occurrence, it should be looked at as a slight tilting of the odds in favor of that outcome.
Last Updated: 7/6/2017
Climate Prediction Resources
NWS Local 3-Month Temperature Outlook
The links below provide access to global and regional climate predictions.