Rain stopped working

The map I made had rain in it and it worked fine. I released it and played it a few times with friends on another server and it worked fine. But we played it again today and for some reason the rain has disappeared. I haven't touched the hammer file since release and haven't changed the download file in any way either. And I recently got someone to check to see if it was working on their LAN server and they said it still wasn't working, so I doubt it has anything to do with the server not showing the rain.

Does anyone know why this happened and how I can fix it without recompiling the entire thing?

Well I checked and I still have my weather settings enabled. But I created a server with the map and the rain is working for me. I'm not sure if it's because I used the collision model rain or not, but it did work on the server before. So unless they changed the server settings which I don't believe they did, it should still be working.

And it's particle rain.