I can say that if u apply this model to ur weather forecasting system , It will predict it 99% truly in a bunch of trials
99% each time? On real datapoints or reference system? 99% on each property, or on weighted average/ensemble median on properties? How accuracy is calculated? Number of times actual data points hit ensemble? then what about ensemble spread? 99% on which error of measures? That's why I say that "99% accuracy" is marketing bullshit, it doesn't say anything to an engineer/metrologist, because they know that accuracy must be viewed in context of how it was measured and also not a single number.