Could this be done (weather effect thingy)

[omber]

Invisible rolling stock (kind of like the AI brake fix someone made not a while ago), that emits a cloud of snow or water splash in direction opposite to it's movement to simulate the clouds that build up in front of loco's when they go through snow/rain. You'd attach it in front of the locomotive. Maybe use the same technique used to make smoke from locos (it blows away from train when the loco is moving).

 

[nwhitney]

Sure, check out sssjung's log engine. It uses twinkles to simulate water splashing up in front of the log. You could ask him exactly how to implement it. Your script would include checking the weather conditions.
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