Random Season Code in Hammer Editor?

Ok I am not really sure if this is going to come out the way I want it lol. But anyways here I go and sorry in advance if this is the wrong thread. So here is my question. I was thinking about this today in Hammer Editor is there a way to change the environment automatically in your map like TF2 does on there menu area before you load the game.

So lets say its Spring Time we can have the sun shining and everything else. Then fall hits we can have it fall and gloomy looking. Winter comes you see the snow falling. I know we can do this making different maps but I was wondering if there was a code to make this automate so the game it self can tell what season it is.

Sorry if I sound confusing but I was not sure how to ask about this. Basically what i am trying to ask if there is a Automated Season Environment Code that will change the settings in the current map without having to change it in hammer.

Again sorry about this if its in the wrong post didn't see a help request thread

Thanks!

Yes, I am talking about the Halloween themed backgrounds on TF2. But as you guys stated its more work then its worth and there is not really a quick or good solution to add this. I think dynamic environments would be awesome in mapping but coding wise seems to be to much of a hassle. At the time guys I didn't even know what i was trying to say I had it in my head but I just didn't know exactly what it was called. But thanks for that. Maybe the year 2020 we can have this feature lol.

P.S. It was just an idea that came to me didn't mean to confuse everyone. Maybe someday the community will write a code or steam will eventually update hammer maybe. Anyways thanks for the suggestions but for now I will just make random maps with random skys lol.