system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What does it take to make it snow? How come there are countries that never seen snow before?

Im asking because where I’m from ( Baghdad) it snowed for the first time since 1914! Why was this year different? Why hasn’t it snowed before?
gpt
In reality, it is always snowing, everywhere except right on the equator.    


People think that clouds in the sky form rain.  In reality, those clouds are so high up that it is always below freezing, so every single rain, except right on the equator, is actually snow that melts as it is falling.  


Therefore only one thing is required for it to snow--that the snow doesn't melt on the way down (or melt and re-freeze, which makes it sleet instead) Basically as long as the air is cold enough it will always snow instead of rain.  So all that is needed is for it to be cold outside.  


Checking the average temperatures in Bagdad, it simply rarely gets cold enough.  It has to get pretty close to 32F or 0C to have any chance of snowing. In addition, it looks like Bagdad doesn't get a lot of rain.  So in order for it to snow it both has to be one of the few days where it rains AND  at the same time it has to be one of the even rarer days where it gets close to freezing in temperature.   


The chances of both of these things happening at once as just very, very small.  Possible, but small.