You can’t predict the weather. If you could, you would make a fortune at the bookies. The best you can do is say what the weather is probably going to be like. And pronounce on how probable that is.

Both the length of time over which you are forecasting and the changeability of the weather alter how confident you can be. Tomorrow’s prediction will be much better than next month’s. Weather forecasters come in for an absurd amount of criticism because this fairly straightforward point is not understood. What they are giving is simply the best statistical guess. They do brilliantly. But the fact that this guess is not what happens a great deal of the time is pretty much a mathematical certainty.

The conman Colonel Stingo used to play the odds, realising that his marks didn’t understand that forecasting was all about probabilities. He promised racecourses that he would make rain for them, calculating the compensation package to reflect the probability of rain and ensure he always made a profit.

The future of weather forecasting? Come clean. Share the probabilities with the viewers.