Look, it's just a requirement to know the weather 3 months in advance. A lot of money is riding on this: agricultural impacts, shipping, the effect on consumer behavior and power generation requirements. Doing without accurate weather reports 3 months out is just not acceptable. Sure, it's hard, but you have to just do it anyway, because it's so important.

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Except weather reports 3 months out are not reliable, unless they are so vague as to be meaningless. I have frequently encountered people who claim to be able to give accurate software estimates. Inevitably, this means that they simply know how to cut requirements as the promised ship date arrives. Which is a useful skill, but not the same as accurate estimates. I have stopped arguing the point, because it doesn't matter what the reality is, business concerns mean that an estimate is required sometimes. But it doesn't mean anything more than the weather estimate for 3 months from now. If you got it right, you were mostly lucky.