Then just a regular El Nino.
And now they just don't talk about it anymore.
Good reason... the famed El Nino has flamed out, and its impact on NW weather is minimal at best.
El Ninos are associated with substantially warmer than normal water in the eastern tropical Pacific. Meteorologists pay particular attention to the sea surface temperatures (SST) in the Nino 3.4 area (see map below)
Here is the plot of the SST anomalies (difference from climatology--or normal). After peaking to a modest 1C, it is dropped to about .5.
NOAA has put a lot of buoys out in the tropical Pacific that are capable of measuring water temperatures below the surface. As shown by the following plot, cooler water has become established under the eastern Pacific. (The figures has depth on the y-axis and longitude on the x-axis, crossing the Pacific from west to east). Not suggestive of an El Nino.
The latest NOAA probabilistic El Nino forecast give a probability for El Nino of around 55% now and that declines over time, with a nearly equal chance of experiencing a neutral year, when SSTs are near normal
With a no-show El Nino this year, the associated atmospheric circulation patterns have not occurred, like a weakened equatorial trade wind and heavy rains over southern CA.
Instead of an El Nino pattern, high pressure has locked on the west coast and that will certainly be the case this weekend as a huge ridge will redevelopment, configured in the classic "omega" pattern:
No comments:
Post a Comment