Heatwaves, tropical cyclones, a high fire risk and what scientists are warning to be the hottest year in human history.

This is what Australia is in for in the new year — and it looks like the severe weather system that will cause all of that is already taking hold now.

The Climate Prediction Centre in the US says there is an 80 per cent chance a full-fledged El Nino has already started.

But while the Australian Bureau of Meteorology (BOM) has us on “alert” for El Nino, it says the system that brings with it hot temperatures hasn’t formed just yet.

As a result of global warming, weather experts are predicting 2019 could be the hottest year ever as temperatures continue to climb.

The 20 warmest years have all been in the past 22 years, according to the World Meteorological Organisation (WMO), with the top four in the past four years.

It’s recent “State of the Global Climate” report warns if El Nino develops, 2019 is likely to be warmer than 2018.

Across the world 1600 people died from heatwaves this year.

And no one under the age of 32 has ever experienced a cooler-than-average month.

“Every fraction of a degree of warming makes a difference to human health and access to food and fresh water, to the extinction of animals and plants, to the survival of coral reefs and marine life,’’ WMO deputy secretary-general Elena Manaenkova said.

BOM’s latest “El Nino — Southern Oscillation” report has said we don’t have an El Nino yet.

“Trade winds weakened in the last fortnight, leading to further warming in the tropical Pacific Ocean, but collectively, the atmosphere has yet to show a consistent El Nino signal,” it said.

“This suggests that the tropical Pacific atmosphere and ocean have yet to couple (reinforce each other), a process that would sustain an El Nino, and result in widespread global impacts.

“El Nino effects in Australia over summer typically include higher fire risk, greater chance of heatwaves and fewer tropical cyclones.”

A recent report on El Nino’s impacts on temperature, rain and fire in a warming climate suggests these will get worse as the climate continues to get warmer.

There have been 27 El Nino events since 1900, with seven of Australia’s 10 driest years on record during one of those events.

Events can last for as little as six months or as long as two years, occurring every three to five years.

A recent report in the Medical Journal of Australia highlighted how the climate was threatening Australian lives, with heat stress alone costing $616 per employed person per year.

“The first 10 months of 2018 could be described as the world’s climate on steroids, wreaking havoc across the world, continuing the relentless march of setting new temperature extremes, rainfall records, increases in severe tropical cyclones, droughts, fires and sea level rise,” report co-author Dr Liz Hanna said.

“Climate change can be linked to the deepening consequences, the rising human toll, loss of human lives and livelihoods, and further erosion of our children’s future.

“Australia’s climate mayhem, which saw last summer’s extreme heat and drought conditions across NSW and QLD, or the current wild weather stretching form Cairns down to the NSW mid coast, are not isolated events. This pattern is occurring all over the globe. No one can continue to pretend this is ‘normal variability’.”