Bureau of Meteorology Forecasts Warm Winter Across Australia

The Bureau of Meteorology is forecasting winter to be unusually warm across Australia as an El Niño climate pattern is increasingly likely to take hold. Both the ocean and the atmosphere need to reach certain thresholds for the climate driver to be declared, according to the agency.

These thresholds have not been met yet but appear well on their way, with expectations an event will be declared during winter.

The dry signal is expected to emerge mainly in July and strengthen into August. The current forecast for June shows no strong signal for below-average rainfall, according to Bureau of Meteorology senior climatologist Caitlin Minney. Despite signs of an El Niño developing, there are no strong signs that it will be unusually dry for any region this winter.

Parts of New South Wales and eastern Tasmania have already faced a very dry year to date and are in severe to record low rainfall deficiencies. Officials are keeping in mind the potential for further increases in those rainfall deficiencies and are carefully monitoring those regions.

Both day and night-time temperatures are very likely to be warmer than average across Australia for the winter season. There is also a strong chance these temperatures will fall into the top 20 per cent of all records.

The combination of drier-than-average conditions and warmer-than-average temperatures is not promising for Australia's snow season. However, snow levels can change rapidly based on just one system, as long as there is enough rainfall and the temperatures are cool enough for it to be snowing, according to Ms Minney.

Every El Niño event is different. In some cases the driver has had no impact at all, though it is overwhelmingly associated with lower than normal rainfall during winter and spring months across eastern Australia. The stronger influence there is likely to be climate change, which has caused a long-term decline in cool-season rainfall.

The Bureau of Meteorology's climate model is currently forecasting neutral Indian Ocean Dipole conditions through to early spring. Other international models are forecasting a positive Indian Ocean Dipole to develop.