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Statistical Accuracy of Internet Weather Forecasts

Posted by CowboyNeal on from the betting-men dept.

markmcb writes "Brandon Hansen considers the statistical accuracy of popular on-line weather forecast sources and shows who's on target, and on who you probably shouldn't rely. Motivated by a trip to a water park that was spoiled with hail despite a 'clear sky' forecast, he does a nice job of depicting deviations, averages, and overall accuracy in a manner that stats junkies are sure to love."

2 of 189 comments (clear)

  1. Reliable forcasting method... by AmIAnAi · · Score: 5, Interesting

    I remember some years ago a radio presenter saying that you could achieve greater accuracy than supposed weather forcasters simply by using the assertion: today's weather will be the same as yesterday. Have we moved on from this position?

    --
    Any sufficiently advanced bug is indistinguishable from a feature.
  2. Interpretation of the models is everything by Aliks · · Score: 5, Interesting

    I am not a meteorologist, but I have worked with them a few times.

    Generally the competing weather models will show a range of possible outcomes with various probabilities. You can average across all scenarios and come up with a 60% probability of rain, but the more days out you go more the scenarios diverge, so the less useful a single average will be.

    Most people would not find it useful to hear that "there will be probably be thunder on Wednesday if it remains hot enough, but if it cools down on Tuesday then the thunderstorm will be off to the north somewhere"

    Additionally, a lot of weather conditions are influenced by thin layers of cloud high up, so thin that precise measurements are critical so precise forecasts in one location more than 3 days out are difficult.