Run BIS_Fnc_Rain as detailed on https://community.bistudio.com/wiki/BIS_fnc_setRain via the debug console and watch the water splash effect on ground impacts with snow particles. If this rain water splash effect is generated by the engine then I assume this can be fixed relatively easily. If not then it might be possible to remove this splash effect via some particle removal loop or killing or setting alpha to 0 on the snow particle prior to it touching the ground.
Aside from the aforementioned issue - the default rain texture also needs a more suitable snow particle texture - that looks less like a postage stamp or a white crinkle cut chip :) than a snowflake, "a3\data_f\snowflake4_ca.paa" is better but still not ideal on close up inspection i.e. when it lands on your face mask.