The likelihood of La Niña occurring later this year has increased to 70 percent, according to the latest outlook issued by the Bureau of Meteorology today.

Last week, the U.S. Climate Prediction Centre increased the chances of a La Nina occurring in 2020 to 60 percent. This followed a sustained period of cooling waters in the central and eastern equatorial Pacific Ocean, and strengthening trade winds over the Paficin Ocean, which are both key signs of a developing La Niña.

On Monday, Australia's weather bureau followed suit, bumping its likelihood of La Niña up from 50 percent to 70 percent and issuing a La Niña ALERT. This means that most of the precursors of a La Niña are now in place and its development is more likely than not.

Image: A La Niña ALERT was issued by the Bureau of Meteorology on Monday. Source: BoM

La Niña refers to a pattern of sea surface temperatures in, and winds above, the equatorial Pacific Ocean. Once formed, La Niña typically causes above average rain over large areas of eastern and northern Australia.

A number of forecast models suggest that La Niña will develop during the southern hemisphere spring and may persist into summer.