{"id":197629,"date":"2017-12-11T15:35:29","date_gmt":"2017-12-11T05:35:29","guid":{"rendered":"http:\/\/southburnett.com.au\/news2\/?p=197629"},"modified":"2020-08-09T15:45:14","modified_gmt":"2020-08-09T05:45:14","slug":"bom-forecasts-short-weak-la-nina","status":"publish","type":"post","link":"https:\/\/southburnett.com.au\/news2\/2017\/12\/11\/bom-forecasts-short-weak-la-nina\/","title":{"rendered":"BOM Forecasts Short, Weak La Ni\u00f1a"},"content":{"rendered":"
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The South Burnett was severely impacted by floods during Australia’s last La Ni\u00f1a event, but BOM forecasts another La Ni\u00f1a this summer will be shorter and weaker (Photo: Peter Verbakel)<\/figcaption><\/figure>\n

December 11, 2017<\/strong><\/p>\n

The Bureau of Meteorology (BOM) has upgraded its ENSO Outlook to forecast a La Ni\u00f1a event this summer, but predicts it will be weak and short-lived.<\/p>\n

On December 5, BOM said signs of a La Ni\u00f1a in the equatorial Pacific increased during spring.<\/p>\n

The Bureau said the central to eastern tropical Pacific Ocean had cooled steadily since winter, and is now at La Ni\u00f1a thresholds (ie 0.8\u00b0C below average).<\/p>\n

Atmospheric indicators including the Southern Oscillation Index, trade winds and clouds also showed clear La Ni\u00f1a patterns.<\/p>\n

But in order for 2017\u201318 to be classed as a La Ni\u00f1a year, the event needs to last for at least three months.<\/p>\n

“Climate models surveyed by the Bureau suggest that while this event is likely to persist over the southern summer, it will be weaker than the strong La Ni\u00f1a of 2010\u201312 and should dissipate by early autumn,” a Bureau spokesperson said.<\/strong><\/p>\n

La Ni\u00f1a typically brings above average rainfall to eastern Australia during late spring and summer.<\/p>\n

However, sea surface temperature patterns in the Indian Ocean and closer to Australia are not typical of a La Ni\u00f1a event, reducing the likelihood of widespread above average summer rainfall.<\/p>\n

La Ni\u00f1a events can also increase the chance of prolonged warm spells for southeast Australia.<\/p>\n