NINO3.4 Index
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.
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Weather News
Late-spring heat gripping NSW
14:59 EDT
New South Wales is baking today as temperatures soar more than 10 degrees above average in some areas.
Double heat for Sydney
19:26 EDT
Two rounds of hot weather during the next week will pack out beaches and pools across the Sydney Basin.
Central Melbourne gets a tree change in readiness for hotter climate
19:09 EDT
Central Melbourne's streetscape is set for a marked change over the decades to come.
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