The world is sizzling and Australia’s winter is just one of the casualties.

July, the middle of the Northern Hemisphere summer, is on average the hottest month of the year globally and satellite data shows that July 2023 was the world’s warmest month on record.

Last month record heatwaves struck the Northern Hemisphere, but now unprecedented heat is hitting the Southern Hemisphere with the most remarkable temperatures this week in South America.

For Australia unseasonable warmth has been building for weeks, and a lack of cold fronts since late July has allowed temperatures to climb up to 10 above average for eight consecutive days.

The whole of Australia, apart from the WA west coast, was warmer than normal on Wednesday.

On Thursday the most unusual heat was observed over the south-east states and our capitals were bathed in sunshine and the warmest maximums in the middle half of winter in more than a decade:

• Melbourne 19.8C – warmest in mid-winter for 10 years
• Hobart 19.6C – warmest in mid-winter for 20 years
• Adelaide 24.7C – warmest in mid-winter for 48 years (26.6C)

Winter’s spring masquerade will continue across the eastern states on Friday as northwesterly winds carry subtropical air well south.

Sydney is forecast to reach 23C and Melbourne 19C, close to averages that would typically be experienced in the middle of spring for both cities.

‘Fairly grim’ ski season

The winter warmth is no more apparent than across the Alps.

August is peak season when snow depth typically reaches a maximum, but mild weather and rain have eroded the cover during the past few weeks.

A measurement taken by Snowy Hydro on Tuesday showed a natural snow depth of only 16.5 centimetres at an elevation of 1,620 metres, well below the early August average of about 70cm.

The lower resorts are suffering as a result.

Selwyn Snow Resort towards the northern end of the Snowy Mountains is in its first year of opening since Black Summer.

It was forced to close a week ago due to lack of snow.

Ant Myers, who has worked in Thredbo for more than 40 years, told ABC radio on Wednesday he was pessimistic about the current state of the season.

“Things are looking fairly grim here at the moment … we’ve had less than average snow and weather conditions haven’t allowed us to make much snow, so look we are really lacking in the snow department … we just can’t win a trick at the moment,” he said.

Is winter over?

Officially winter still has another four weeks to run, and there’s plenty of time for a few cold snaps, although modelling indicates most of Australia will remain warmer than normal until the middle of August.

In the short term, cooler weather will develop across South Australia on Friday as a cold front pushes a band of rain across the state.

The front and cloudband will drop temperatures by Saturday over Tasmania, Victoria and southern New South Wales, but temperatures well above freezing on the Alps will ensure rain and further damage to the snow cover.

While temperatures will be closer to average for a few days behind the front for southern states, relatively warm air will remain over the rest of the country through next week.

Longer term modelling currently indicates prolonged wintry weather will not return until the second half of August, and hopefully this means regular snowfalls before the end of the season.