Some time ago I saw on the internet how they changed the climate of this campaign and they did it at night. So doing some research I got to know what was going on with the PLUGINS. So here I leave this topic for those who want it.
To achieve that requires 3 plugins.
To be able to change the weather you need this plugin.
1.-
https://forums.alliedmods.net/showthread.php?p=1706054 BY SILVERS
(OPTIONAL)
This plugin is optional to add some lights in some places where it is hard to see, if you don't want it go to the .zip folder and delete the plugin named LAMP as well as its cfg located in the DATA folder.
2.-
https://forums.alliedmods.net/showthread.php?p=1658873 BY SILVERS
This complement is very important, I think that by now most of you know it.
3.-
https://forums.alliedmods.net/showthread.php?t=39439 BY BAILOPAN
Those who do not know the plugin check this link:
https://forums.alliedmods.net/showthread.php?t=39439
If you did everything correctly
Video Demonstration
I would appreciate it for those who want to improve it, share in this same thread for the community 
and make it much better.