In the old days there were no weather forecasts, no weathermen on TV (no TV either) and no daily breakdown of weather and other meteorological issues on every newspaper and web site. I’m sure it does not shock you to learn that in the year 1,400 there were no web sites, no TV and no daily papers. However in parts of Europe there was this thing called the inquisition, which is nothing like weather forecasts.
People who believed (and everyone was forced to believe) had a very strong conviction that it was god who controlled the sky and the seas, it was god who decided if it will rain and therefore if it will be a good harvest year, or there will be storms, floods and heavy snow in winter. That was all god, and it had a very close link to human behavior, simply meaning that if you were good the weather would have turned out nicely for you, and if you were bad you should have prepared for a rough time.
Of course monotheistic religions borrowed the idea of weather and god from the pagans before them, they only thought that the idea of different gods taking care of different elements was ridiculous and somehow it was clear to them that’s its just one god who does everything.
See, in ancient times humans were afraid most of the time, from almost anything, because it meant trouble, disease and death. They did not have any way of telling if and when the sun would rise the next day, if it will snow in August and if night would not fall unexpectedly in the middle of the day for a few minutes. So there was some sense in developing an idea of naughty gods playing around with the weather, but today? when any 12 year old can see what the weather would be like? (well, not exactly how it will be like, but most of the time).
And somehow this not only escapes the minds of believers everywhere, it is so natural for them that today, using science, we can easily predict the weather, that believers have just shifted from the god who controls rains to something a little more dramatic, the god who controls earthquakes and hurricanes, and if one day science will discover a way to predict those they will probably move to another thing.