The NINO3.4 index is one of several El Niño/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 Niño 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 Niño or La Niña event is identified if the 5-month running-average of the NINO3.4 index exceeds +0.4°C for El Niño or -0.4°C for La Niña for at least 6 consecutive months.
Overnight, Melbourne experienced very warm temperatures under a blanket of cloud ahead of a cold front.
There are few things farmers enjoy talking about more than weather, even if it's bad news, but it's not just farmers who have a keen eye on the skies.
The weather bureau details the seasonal outlook for Tasmania and whether any extra rainfall is on the horizon
The weather bureau has released its latest seasonal outlook covering the three months of spring which says there are no strong indications for extra rainfall.