Apparently We Can Now Forecast the Weather a Year Before It Happens

There was a time when the British weather forecast consisted largely of a cheerful person standing in front of a map and telling you it might rain in Birmingham on Wednesday.

This seemed reasonable. Wednesday was already quite ambitious.

Now the Met Office is discussing what a potentially extraordinary El Niño could do to weather patterns months into the future. Its scientists say the developing 2026 event could be the largest in living memory, with an unusually intense signal showing up across forecasting systems.

We appear to have gone from:

“Take an umbrella tomorrow.”

to:

“There are some rather interesting things happening in the Pacific which you may wish to bear in mind next spring.”

Before anybody buys twelve bags of rock salt, there is an important distinction.

The Met Office cannot tell us that it will rain in Chelmsford at 3.17pm on 14 February.

Day-to-day weather becomes increasingly difficult to predict beyond roughly a week or so. What scientists can sometimes see much further ahead are slow-moving forces in the climate system—particularly changes in ocean temperatures—which alter the probability of certain sorts of weather occurring. El Niño is one of the most important of these.

So this isn't really a forecast.

It is a warning.

And there is an enormous difference.

Five hundred years ago, Desiderius Erasmus understood something rather similar.

Erasmus grew up in the Europe of the late fifteenth century and lived into an age of extraordinary political and religious upheaval.

He wasn't a prophet.

He did not sit down in 1498 and write:

Luther, 1517. Henry VIII, complicated. Thirty Years' War, allow plenty of time.

But Erasmus was exceptionally good at noticing conditions.

He saw ambitious rulers surrounded by flatterers. He saw princes pursuing prestige through wars whose costs would fall primarily on ordinary people. He saw nationalism, religious antagonism and institutional rivalry hardening.

In The Education of a Christian Prince, written for the future Emperor Charles V, Erasmus warned rulers about the seductions of conquest and urged them to calculate the real costs of war before embarking upon it. In The Complaint of Peace he returned to the same theme: small rivalries, vanity and political ambition had a habit of producing consequences considerably larger than the people initiating them imagined.

And in 1517, as Europe approached the Reformation, Erasmus wrote privately that he feared a great upheaval was coming.

He could see the pressure changing.

He just couldn't tell you precisely where the storm would break.

That is rather close to what sophisticated forecasting actually looks like.

Three Wise Things to Do When Someone Warns You About the Future

1. Don't confuse probability with prophecy

If someone says there is a 70% chance of something happening, and it doesn't happen, they weren't necessarily wrong.

There was a 30% chance it wouldn't.

This is surprisingly difficult for human beings to accept.

We want experts either to KNOW or NOT KNOW.

Unfortunately, most of life happens between those two settings.

The Met Office's long-range forecasts therefore talk about likelihoods, not certainties. Ocean temperatures and other large climate drivers can shift the odds without determining precisely what Britain's weather will do on a particular Tuesday.

Good forecasting is often less like announcing tomorrow's lottery numbers and more like noticing that somebody has quietly placed six banana skins on the stairs.

You cannot know who will fall over.

You can reasonably suggest holding the handrail.

2. Prepare while preparation is still cheap

This may be the most useful principle of the lot.

Warnings are valuable because they arrive before action becomes urgent.

If there is a reasonable possibility of disruption, you do not necessarily reorganise your entire life.

You make the inexpensive preparations.

You check the insurance.

You back up the computer.

You put a torch somewhere you can actually find it.

You leave slightly more money in reserve.

You buy the train ticket before everybody else discovers there is only one service running.

Erasmus's frustration was that Europe's rulers repeatedly waited until rivalry had become war before becoming interested in peace.

Preparation is almost always cheaper on Tuesday than panic is on Friday.

3. Keep updating your view

The wise response to a long-range forecast is not:

“Excellent. We now know what will happen.”

It is:

“Interesting. What does the next forecast say?”

The Met Office itself stresses this. Longer-range outlooks are designed to create early awareness; they should then be updated as better seasonal and eventually short-range information becomes available.

This is also a useful rule for careers, money, politics and almost everything else.

Notice.

Prepare.

Update.

Do not marry your first prediction.

There are enough unhappy marriages already.