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Comment by panarky | Hacker News Reader

> if we build a classifier that predicts the weather in my garden tomorrow based on the history of the weather in my garden it will do very badly

Give me hourly readings of temperature, wind speed, wind direction, precipitation, cloud cover and barometric pressure for the last 10 years and I can give you a very accurate prediction of tomorrow's weather in your garden.

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Hello, interestingly governments and private industries have invested a very large amount of money in the launch of satellites, development of supercomputers and code and the training of forecasters to interpret them.

Many years ago I actually seriously tried to do what you describe above, I tried out all sorts of things around seasonal analysis and other features. What kills it is the chaotic nature of UK weather due to the jetstream and NAO.

is that a joke? weather predictions are notoriously unreliable even though they are given with extreme granularity.

that aside you are missing a larger point. if you predict the future based on past data all you are saying is "the future will be the same as the past." you aren't predicting anything. you will be wrong every single time something novel occurs, which is pretty frequently in the real world.

The perception that weather forecasting is notoriously unreliable is mostly false: https://mobile.nytimes.com/2012/09/09/magazine/the-weatherma...

From your link : "Why are weather forecasters succeeding when other predictors fail? It’s because long ago they came to accept the imperfections in their knowledge. That helped them understand that even the most sophisticated computers, combing through seemingly limitless data, are painfully ill equipped to predict something as dynamic as weather all by themselves. So as fields like economics began relying more on Big Data, meteorologists recognized that data on its own isn’t enough."

Quantifying uncertainty is one of the main points of statistics. Don't confuse the limitations of point estimates provided by machine learning techniques with all of statistical practice.

i am not sure what that article is supposed to prove. it doesn't contain any study results on the accuracy of meteorological predictions.

I don't have the data handy but to the best of my recollection weather forecasting for high/low temperature and precipitation does pretty well for the range of 24-48 hours but declines steadily in accuracy, and is no better than random guess around 2 weeks out.

That said, you are not addressing my other point, which is that "weather prediction" is just saying "things are going to stay the same." You are always starting with a set of conditions and then looking at your records and seeing what happened in similar conditions and predicting that the same thing will happen again.

Predicting that things will stay the same may come out as better than random guess in many cases but it will still be 100% wrong in cases where something novel happens.

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