Thanks Bob, especially the hovmoller explanation. This is proving to be a fascinating puzzle.
A few interesting things have happened since the July Update last week. On the ocean side, weekly sea surface temperatures in the NINO3.4 region have dropped (just) below the threshold of El Niño conditions (using the standard NOAA base years of 1971-2000 for their Reynolds OI.v2 data). On the atmospheric side, the 30-day running average of the BOM Southern Oscillation Index (SOI) has finally neared the threshold of El Niño conditions. But the SOI does not reflect what’s going on along the equator. And there is evidence that the trade winds are slightly stronger than normal across most of the equatorial Pacific.
View original post 1,246 more words