Astrology - Basic Criteria for the Predictions

Once an astrologer said, there is going to be a big fire in the next few days. 

After a few days, he said, there was a big fire in Pakistan, and he claimed his predictions were correct.

This made me think of the evaluation of a prediction. 

What I feel is, for a prediction to be of some sense, by following the prediction, we should be able to take some decision or change a decision or atleast give more or less confidence in the decision that we are already taking. If it does not give any of them, then that prediction is useless. 

Once I went to Mumbai and it rained a lot. All the trains and flights got cancelled, and there was a lot of water on the road and travelling even by the road was not possible. I faced a lot of difficulties, cancelled all my plans, and it costed me a lot. If someone had predicted that I would face difficulties if I go to Mumbai, I would have saved a lot of money. 

That prediction does not need to be from an astrologer who looks at Horoscope charts or palm. It can be somebody who can look at the weather report of Mumbai, and who knows that, whenever there is a lot of rain, Mumbai would be flooded and the trains would be cancelled. 

It does not matter how I get the predictions. By that prediction, I should be able to take a decision or change the decision or should change the confidence level of the decision that I was taking.