M: Well, you didn't expect it to be warm, did you？
W: Of course not, but I heard the national weather service's prediction for the next 90 days. They said it' s supposed to be much colder weather than usual.
M: Yeah, maybe. Personally, I think those long-range forecasts are useless.
W: Not as useless as you think.
M: Oh, come on, when you' re talking about what' s going to happen three months later, you might as well just pick a forecast out of our hat.
W: Well, you are partly right. They area' t very good at the amount of water falling on the earth. But they are much better for temperatures especially for this time of the year.
M: Really？ So I should take them seriously about the cold but not count too much on a lot of extra snow？
W: Exactly.
M: But what did you say about this time of the year？ Do some seasons really give them more problems in making forecasts？
W: Autumn is the worst; apparently weather patterns change so much then. Just think how variable our weather has been the last three months.
M: Come to think of it, that' s true. It probably would have been hard to predict all those chan ges back in the summer. You know, you' re beginning to convince me there is more to fore casting than I thought. How come you know so much about it？
W: I get my information from an expert--my sister.
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A. The foundation.
B. The reliability.
C. The history.
D. The source.