The Bureau of Meteorology will no longer issue fortnightly updates including La Nina and El Nino watches and alerts, or publish a dial showing swings between the climate drivers, as historical experience becomes a less reliable future indicator. 

The climate driver updates will be replaced by the southern hemisphere monitoring page, in combination with outlook pages.

The bureau is encouraging people to follow its short- and long-term forecasts and says the changes will help it provide the most relevant and accurate information based on “whole of system” observations, modelling and more precise predictions.

Climate manager Karl Braganza says old methods of prediction have become less reliable, and new models based on current information are a better way to help the community and industry prepare for seasonal trends.

“We are moving away from focusing on individual environmental phenomena,” he said. “In a changing climate, it is more difficult to make predictions based on events when they are looked at individually – climate systems are complex and cannot be explained by just one influencing factor.”

The regularly issued and updated 90-day forecasts are the best guide for likely rainfall and temperature in the weeks and months ahead, Dr Braganza says.

Bureau long-range forecasts are informed by a physics-based model that takes in atmospheric and oceanic observations including greenhouse gas concentrations. It also keeps track of climate system changes and ocean and atmosphere conditions that influence seasonal weather.

The southern hemisphere monitor and outlook web pages will include data on relevant environmental phenomena such as the El Nino Southern Oscillation (ENSO), Indian Ocean Dipole, Southern Annular Mode and Madden-Julian Oscillation.

La Nina conditions have historically been linked with wetter weather and increased flooding for much of eastern Australia, while El Nino is associated with drier conditions and an elevated bushfire risk.

A recent climate driver update noted that global sea surface temperatures had remained near record levels and the sustained nature of global ocean heat suggested indicators such as the ENSO and the dipole may not behave or evolve as they have in the past.

The bureau on Thursday said rainfall for the remainder of December is “likely to very likely” to be below average for much of NSW, Victoria, Queensland and eastern SA.

January rainfall is likely to be within the typical range for large areas of the country, with February and March showing a broader wet signal.

Above average maximum temperatures are “likely to very likely” for most of Australia in January to March.