In the famous story 風の又三郎, the sound どう is used to describe the wind in several places, including the song in the intro.
One such place is:
I did some research, and it seems that 「どう」 is not a normal way to express the sound of wind in Japanese. I have heard that Mr. Miyazawa is "a master of onomatopoeia" so I guess he made this expression up himself.
However, no matter how I think about it I cannot seem to match any sound of wind I have heard before with "doh".
How to Japanese people interpret this? Is this supposed to be the sound of something slapping against something else due to the strong wind?
If it was "dooooooh" I might understand it as a blowing sound, but it is always short, especially in the introduction song, which I have heard read very quickly in readings. So it seems more percussive than blowing.