Simone Visciano

Add elegant snow effects to your WordPress site with optimized, lightweight JavaScript. 
Designed for mobile and desktop, it self-manages animation performance to prevent lag, keeping your site fast and smooth.
Many aspects of the snowfall behavior are fully customizable, including falling speed, wind, depth effect, rotation, random gusts, density, turbulence, scroll with page, z-index, and more. 
To make customization quick and easy, you can also choose from ready-made presets, either using them as-is or starting your personalized snowfall from these.

SVisciano – Snowfall Effect

Add a festive winter touch to your WordPress site with realistic, lightweight falling snow animation.

WinkingFrog

This is a straight forward Plugin that does not require the use of any shortcodes or widgets. Simply head for Settings > WFS Let It Snow and configure your snow flurry! This plugin makes use of Jason Brown’s brilliant jQuery plugin <a href="http://loktar00.github.io/JQuery-Snowfall/" rel="nofollow ugc">Snowfall</a>, all credit for the snow effect must go to Jason! This is being distributed as a FREE plugin from Winking Frog Studios, we hope you all have a wonderful festive season!
There is a really good chance this plugin will work with earlier versions of WordPress, but the chances are an active site will be at WordPress 4.0 or higher anyway.
<h3>Plugin Usage & Shortcodes</h3>
Once installed and activated you will find a ‘Let It Snow’ menu item in your Settings. The settings for the plugin are all very straight forward, just play around with them until you get the desired effect.
Developed by <a href="http://winkingfrog.com" rel="nofollow ugc">Winking Frog Studios</a>

WFS Let It Snow

A super simple plugin that adds some seasonal snowfall to your website.

SVisciano – Snowfall Effect vs WFS Let It Snow