Neutral ENSO conditions presently exist in the tropical Pacific, but an El Niño is likely by spring if present warming rates continue. Over the July to September period, circulation in the New Zealand region is likely to show a transition from the more 'blocked' north-easterly anomalies persisting from the recent La Niña towards a zonal westerly flow at the end of the season as El Niño conditions settle in.
Sea surface temperatures
Sea temperatures around New Zealand are likely to be near normal for the season as a whole.
Differences from average global sea surface temperatures for 3rd June to 30th June 2012. Map courtesy of NOAA Climate Diagnostics Centre (http://www.cdc.noaa.gov/map/images/sst/sst.anom.month.gif).
Monthly values of the Southern Oscillation Index (SOI), a measure of changes in atmospheric pressures across the Pacific, and the 3-month mean (black line). SOI mean values: June SOI -1.2; April to June average -0.8.
Differences from normal June surface temperatures in the seas around New Zealand.