Eastern Australia and parts of the southwest are likely to receive below-average rainfall from May to July, the Bureau of Meteorology says in its latest long-range forecast.

Most of the southern two-thirds of Australia have an increased chance of unusually high maximum temperatures, with the highest chances across much of NSW, southern Queensland, Victoria, eastern Tasmania and southwest WA.

Sea surface temperatures are forecast to be warmer than average across much of the globe, while the El Nino Southern Oscillation is currently neutral.

“For the tropical Pacific, models suggest a possible shift to El Nino by later winter. However, there is still uncertainty around its timing and strength, with a clear picture expected as autumn unfolds,” the bureau said last week.

The dry and warm outlook and and the potential for an El Nino, associated with drier weather in eastern Australia, raises bushfire concerns for insurers.

The World Meteorological Organisation said on Friday that sea surface temperatures point to a likely return to El Nino conditions as early as May-July.

“After a period of neutral conditions at the start of the year, climate models are now strongly aligned and there is high confidence in the onset of El Nino, followed by further intensification in the months that follow,” WMO chief of climate prediction Wilfran Moufouma-Okia said.

Models indicate it may be a strong event, but a “so-called spring predictability barrier” is a challenge and confidence generally improves after April, he says.

See ANALYSIS.