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.
The month of July was quite dynamic across the nation, with some particularly strong cold fronts which delivered low level snow as far north as the Border Ranges, and spells of prolonged dry and warm conditions, particularly along the east coast.
Widespread, drenching rain across many parts of Western Australia's agricultural region, brings a smile to the faces of local farmers.
Some encase Darwin's homes in a gnarled mesh vestige while others stand like spiked watchmen separating the street from those living inside.