How to make rain particle system cover my entire map?

I am making a multiplayer open world survival game that has a very large map, but I cant seem to figure out how to apply my rain particle system to my entire map. My particle system has a initial location node that I can set to cover a huge area, however, when I do this, the rain particles get dispersed evenly throughout the area which in turn makes them hardly visible, all you can see is a single rain drop from time to time. I have tried increasing the particles spawn rates but that does not work properly because I have to set the spawn value to some insane value like " 8,000,000,".
and setting a value this high causes the rain particles to be spawned in a single dense burst, then it stops and it spawns another burst after a few seconds. No matter what I do I cant get this working and there is not much info out there about how to make rain cover large landscapes, every tutorial about making rain is intended for a single player game in which the rain particles simply follow the player around. What I am doing wrong?

wouldnt players be able to notice that there is a patch of rain that is following around the other players?

I believe the rain particles are cosmetic so single player approach still applies.
You only need one rain particle on each client.

No, because the particle is on client side, so each player will see only their own rain.