The NINO3.4 index is one of several El Niņo/Southern Oscillation (ENSO) indicators based on sea surface temperatures.
NINO3.4 is the average sea surface temperature anomaly in the region bounded by 5°N to 5°S, from 170°W to 120°W. This region has large variability on El Niņo time scales, and is close to the region where changes in local sea-surface temperature are important for shifting the large region of rainfall typically located in the far western Pacific.
An El Niņo or La Niņa event is identified if the 5-month running-average of the NINO3.4 index exceeds +0.4°C for El Niņo or -0.4°C for La Niņa for at least 6 consecutive months.
Saturday's storms produced large hail, intense rainfall and destructive winds to several locations across southeast Queensland as two large storms rolled over in quick succession.
Two homes in south-east Queensland were destroyed by fire during yesterday's super cell storms, which also overturned caravans and saw a teenager struck by lightning.
Parts of far northwestern New South Wales have been scorching in temperatures in the mid forties, as much as 10 degrees above average.