WE’VE all been there. The weather forecast tells you it’s going to rain and it’s actually glorious sunshine. They say we’re going to bake and we get drenched.

But the forecasting fraternity has hit back saying weather reports have never been more accurate.

What’s more, a project is under way to predict major weather events year — even decades — out.

A “quiet revolution” in meteorology is taking place, weather boffins say, combing big science, mathematics and some very large computers.

If they’re successful, it could lead to extreme weather forecasting that could provide much richer detail months out and even an indication of major weather events years out.

The experts even claim the results could save lives.

Currently, weather forecasts of any detail stretch out to about a month. But more than a week out, their accuracy can diminish and after 28 days generally only overarching weather trends are predicted.

“If anyone says right now that there will be a big El Nino in 2022, I wouldn’t trust them. But at the moment we’re doing the research to see if that might be possible,” Peter May, head of research at the Bureau of Meteorology, told news.com.au.

On Monday, Dr May spoke at an Australian Mathematical Sciences Institute event at Brisbane’s Queensland University of Technology about efforts to super charge medium to long range weather forecasts.

Despite the doubters, he says our weather forecasts are generally on the money.

“Our forecasts, seven days out are now more accurate than three-day forecasts were 15 years ago. To me, that’s staggering and that been done through massive international collaboration.”

Nevertheless, the basic method of weather forecasting hasn’t changed much since pioneering British mathematician Lewis Fry Richardson devised his “numerical process” in the early 1920s.

Up to that point, meteorologists would look for similar past weather events to the one due and then take a stab at whether that meant it would be a hot or cold day, if there would torrential rain or stifling heat.

Instead, Richardson used a mathematical model, employing data including surface temperature measurements from all over Europe communicated to the UK via telegraph.

“The basic idea hasn’t changed in 100 years but our ability to do it has changed enormously with increasing amounts of data — from weather balloons, commercial aircraft as they fly along, satellite measurements, how fast cloud moves, how much the earth glows infra-red, radio waves the earth emits, and that has allowed us to create higher resolution and finer scale models,” said Dr May.

Increasingly, he said, meteorologists use a technique called “ensemble forecasting” where a range of possible weather outcomes is plotted so you know what’s most likely but can prepare for the worst.

“You can’t say there will be cold front on, say, August 3, but you can say there is a more than average chance of what the cyclone risk in four weeks and that’s useful,” said Dr May.

“The aim is to equip forecasters with the best possible information so the person on the street and industry all benefit and it makes people safer.”

Dr May’s team are now researching if the ensemble method can be used to predict weather events far into the future. By entering in variables, such as possible climate change scenarios, they can test different outcomes.

“We’re making use of big data, four petabytes that’s as much as eight million laptops and we need the equivalent of 20,000 laptops joined up to generate that data,” he said.

It could lead farmers to move livestock around that might be at risk, for emergency services to bolster civilian cyclone defences or prepare for bushfires.

“So instead of our farmers gambling with the weather, this could turn them into bookmakers. There might still be uncertainty, but in the long run, you have the information to win.”

To test the new style forecast’s accuracy, Dr May’s team are first seeing if it could have predicted major weather events over the past century.

If the model’s forecasts and the actual historical events marry up then a new form of long range extreme weather forecasting could be born.

“In a perfect world, our model would predict the La Nina that ended the millennium drought.

“If the model world behaves similar to what we’ve actually observed then that give us confidence in our projections for future.

“We’re optimistic for some of these big events, like a big El Nino, we can predict them.”

If all goes well, alerts to the possibility of a major weather event in five to 10 years’ time — or even further into the future — could be issued by the bureau or other weather agencies.

Dr May warned the research was still “very experimental”.

“It’s about providing information to make smart decisions and play the odds with the weather. We’re trying to load the dice to make it work in your favour.”

But, he warned, there are limits to what even the most dedicated weather boffin, with a whole heap of petabytes at their disposal, can forecast.

“We’re a long way away from being able to accurately say it will be a wet winter in, say, 2030.”