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Understanding the Weather

What is the Nino3.4 Index?

The Nino3.4 Index, similar to the Southern Oscillation Index, is closely tied in with the El Nino phenomenon. Nino3.4 is the average sea surface temperature anomaly in the area bounded by 5N to 5S and 170W to 120W. Changes in sea-surface temperatures in this region are important in shifting rainfall areas across the far western Pacific Ocean. An El Nino event is indicated if the 5-month running average of the Nino3.4 index exceeds 0.4C for at least six consecutive months. A La Nina event is indicated if this average is below -0.4C for at least six consecutive months.

A graph of the Nino3.4 index is updated weekly on Weatherzone, making it easier to track changes in the Pacific Ocean sea-surface temperatures.

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Bonsoy Gold Coast Pro surf forecast

07:00 AEST After an emotional mid-year cut at the Margaret River Pro surf competition in Western Australia last week, surfers that fell below the cut line, along with up-and-coming talent, will be battling it out on the Gold Coast from this weekend onwards.  The first stop on the Challenger Series (the lesser format of the Championship Tour) will take place along the Gold Coast’s premier surf point breaks, starting this morning and running to Saturday May 4th.

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