How to Make a Rainy Window in Blender
Why Blender Stack Exchange recommends it
Blender Stack Exchange answerers point people to it when someone wants to create realistic raindrops or water droplets on glass.
Recommended by 3 people across 3 different months, 2016 to 2019.
What it is
A roughly 49-minute Blender tutorial by Andrew Price of Blender Guru that walks through building a rainy window scene. It covers modelling water droplets, setting up glass and droplet materials, and using dynamic paint to create the effect.
What people said
Recommends Mörkö · 2016-08 · Blender Stack Exchange · on “Creating a rain effect”
If video tutorials are your thing, Andrew Price has made one on both types of rain. Here is one for the big drops on a window: [this video] Here is one for the splashes onto wet ground: [LINK] (This is slightly outdated as it is for the internal renderer, but I think that the dynamic paint itself is applicable to cycles too.) Edit: Due to popular demand I will try to summarize the tutorials here. I skip the part about raindrops with trails, as your reference doesn't show any. I will also skip the compositing and lighting part of the tutorials. Close-up raindrops Modelling and materials Start with a UV Sphere. Rotate it by 90° and in edit mode select one of the poles. Hit o to go to proportional e
Recommends Patdog · 2017-04 · Blender Stack Exchange · on “How can I make the clear trails left behind by water droplets?”
Boundless Blending has a procedural rainy window texture that you can download and study [LINK] - also Blender Guru has a tutorial on creating this effect [this video]
Recommends TheCatalyst · 2019-04 · Blender Stack Exchange · on “How can I make drops of fluid hang from a surface?”
The best way that I know of to do this, assuming you just want a still, is to do it through metaballs. Set up the object with the metaballs so that they diffuse onto the glass, but remain off from it enough to look like a droplet. If you do multiple of them, you can animate them, although it will not look the most realistic. Alternatively, use this tutorial [this video] on how to make a rainy window, and apply it to the effect that you want.