With renewed interest in La NIña I have updated the graphics depicting the Oceanic Niño Index (ONI). Most notably and to make the data more readable, separate time-series graphs for the periods of 1950-1989 and 1990-present have been added. This is in addition to the previous 1950-present time-series. See https://ggweather.com/enso/oni.htm.
Jan Null, CCM
Certified Consulting Meteorologist
Golden Gate Weather Services
Phone: (650) 712-1876