If you are old enough to surf the internet by yourself, you know what windshield wipers are, don’t you?
Joke on the side, let’s answer the question.

Do trains have windshield wipers?

Short answer: Yes they do and in fact they are heavily used, especially for trains operating in states with heavy snow/ rain fall, not as much in SoCal.Long answer…
Trains have windshield wipers, in fact their windshield wipers are car windshield wipers on steroids, many locomotives use “heavy-duty” style wipers powered by compressed air.

Why is there a long answer for this question?

Well, it is not necessarily a long answer, but a more detailed one, that I believe you will find useful.
Trains didn’t always have windshield wipers, steam locomotives which were heavily used between the early 19th century and middle of the 20th century didn’t have these devices. First models of street cars didn’t have them either.
Today every train I have researched has windshield wipers and I believe it is required by the law that every operating train has to have them.In tandem with these devices, many newer locomotives are equipped with heated windshields, meant to melt any snow/ ice that might build on it.