Good one!

Yes, it is!

I'll go with the weather forecasters for now. They have computer models that they use to forecast the weather. A case in point, is when a local forecaster showed a weather map projection at 6AM, about a huge black cloud showing up over my city at 12 noon. The sky was clear as a bell until 12 noon and then this huge black lumbering cloud came over our city.
In the morning I see the cloud on tv and at noon I see it over my house.

west gardner, your weather forecasters must have better computers than ours! More often than not--at least it seems that way--what they've forecast doesn't materialize, not in the form of raindrops, anyway. :>(

It's probably more than the computer in play. It can depend on what other resources a forecaster has available. Weather satellite access feed, radar feed, computer models, at least that's what the forecasters mention during the tv segments. I imagine that the education and training of the forecaster to use the information comes into play.
Your statement about the rain drops hits a chord, because one of the forecasters said some of the of the clouds goes under the radar and he asks his audience to twitter or email him when they see some "drops". It's not perfect, but it works for me.